Oh, to be William Shatner, eh? To live in some curved glass Malibu dream home with a sunken lounge (just guessing, but it feels right), those staircases which are only attached on one side, and an over-stuffed Victrola-cabinet-stroke-bar lavishly stocked with Disaronno and the very choicest Mantovani LPs. Could life get any better for The Shat? Wait! Here's Facebook, emailing about Mentions, a new celebrity-only app that allows the anointed to...to... well, maybe I don't know exactly what it does, but it must do something incredible, right? Mariah Carey's involved. 'Sign me up, Scotty!' says Shatner, his words echoing off the glass and the Disaronno, until silence descends and he's lost in reverie - back auditioning for TJ Hooker, perhaps, or performing Hamlet at a technical college in Winnipeg.

Mentions is actually sort of interesting - and it's interesting, I think, purely because it's an app that most of us will never get to see or to use. It's like the fabled celeb-only Nando's card - always a bit of a strange one, this - that many conspiracy theorists postulate may allow the fabulously wealthy and beloved to dine for free in the kind of restaurant that usually makes you queue at the till to place your order. I'm not sure Mentions is truly even that brilliant. Setting aside Shatner's negative online review, there's the hollow echo of a Beckett production to it: a chat room largely filled with people who have guest-starred on Columbo. Then there's that old Groucho Marx zinger about never wanting to belong to a club that would have Ed Sheeran as a member. But who cares? This is an app you can't buy, and yet aren't apps meant to belong to that glorious class of things you can have any of for the right price?

Shatner, back in his Boston Legal days.

The grim appeal of the exclusive isn't new to games, but taking it this far probably would be. Facebook's essentially just put in a poor door that we're all expected to shuffle in and out of knowing, just knowing, that we're tucked away by the bins while Shatner and Sheeran are screwing about in a marble lobby. They're probably collaborating on a song in there! Awful as this all is, and as much as it calls to mind the dizzying chinoed horror of an Elite Singles TV ad, in my darker moments it's made me hanker a little for more genuine customer-hating exclusivity in games. Not the pre-order exclusives which are always either too crap to worry about or so great that they'll eventually turn up as DLC, but honest-to-Betsy you'll never play this unless exclusivity, where the unfairness of it all only makes the thought of possession sweeter. We want what we can't have: it's a huge part of what makes us human. It got us to the moon. Isn't there a strange innate appeal to the idea of a game that almost nobody will get to play?

Back in the days where all media was physical, this was a little more common, of course, if not through design. Radiant Silvergun was a game that most of us would never get hold of, at least not without a dinged-up spine card ruining the lustre. But I'm guessing that was never intentional - the publisher just probably didn't think it was worth making too many copies and being lumbered with all that overstock. Now Radiant Silvergun is available as an XBLA game anyway. I'll admit something terrible here: when I couldn't have Radiant Silvergun, I used to sit and wonder what it would be like to play it. Now I can play it, I haven't even downloaded the trial. (Yes, this is stupid of me, not least because I gather it's wonderful. I also haven't ever played that free Prince album I once had to buy the Daily Mail to get, incidentally.)

Speaking of downloadable games, though, I have got Robotron: 2084 on my Xbox 360. It's been delisted, though, so if you missed it you can't now go and buy it - and I can't even share the purchasing link with you because that option's been delisted too. I love the 360 version of Robotron, despite the horrid new graphics and the pad with those mis-aligned sticks. I loved it before it became a genuine exclusive, because it's essentially the greatest game ever made, but I have to admit that now, I perhaps love it a little bit more. Or at least a little bit differently.

Somebody should harness this odd kind of involuntary love. You could probably even make a business out of it. Seriously: each time I've come across a game that's a genuine not-available-for-everyone proposition, the love has been the same. There's Shader, that game made by Colin Northway, which he's ensured will never leave the laptop it was coded on. Man, I want to play that, and Steven Totilo's wonderful piece pondering the allure of the truly rare made me want to even more. A game that's not only an exclusive, but is fated to die along with its hardware? Yes please. "In an age of constant recording and copying, impermanence is novelty...." writes Totilo. "[Shader's] a game you or I can only play if our lives take us certain places and enable us to meet a certain person." Isn't the very unfairness of that perversely appealing?

Closer to home, a little while back, I received a preview build of a brilliantly unusual iOS roguelike that was cancelled shortly after the code was sent to me. I played that game with extra fervour for a whole year after that until the preview build expired, and I even bothered writing the rules down so I'd be able to remember them properly in the future. Equally, I still haven't deleted Flappy Bird from my phone, despite the fact I've barely played it, and I'm probably not going to. It doesn't matter! I've got Flappy Bird on my phone! Have you? (You probably have, actually, and I think it's now on the Amazon App Store anyway. Hey, maybe I will delete it after all!)

The sweetest case of the strictly-limited-exclusive I ever came across is when ANGELINA designer Michael Cook got his AI to build a game just for my family. It's called Sand Up For, because I live on the coast. Here's a screenshot!

And the weirdest? The weirdest exclusive is something I haven't thought about in years. When I was at university, a friend of mine had a Pentium he'd inherited from his recently departed grandmother. He mainly used it for Word - or for Worms - and rarely ventured into the file directory.

When he did one day, though - I think I had just handed out a savage Worms 2 defeat courtesy of my best ever team, The Benjamins, who were all named after people who had appeared on money, and he needed time to muster a response - he found a copy of QBasic (or an equivalent) and a strange file. He set the file running and weird geometrical shapes spun across the screen accompanied by the sound of a car's steady acceleration. He eventually discovered that he could control the shapes a little with number keys, and modify the tone of the engine revving.

Our eventual conclusion was that this was a sort of game - a sort of programme, at any rate - that his grandmother had been tinkering with after she found herself with a new PC and nothing much to do in the evenings. You couldn't do much with the game itself, actually, and in truth, I don't remember us playing it for very long. Still, it had a wonderfully rare ambience. It felt like a glimpse into a parallel track of evolution: a game made by someone who knew nothing of the rest of games and was fumbling towards them through first principles.

This idea of parallel evolution might have something to it, actually. While there's something inherently elitist and naff about making things like Mentions that are only available for a select few, I think there are lots of positives for games that are made with a somewhat similar mindset - made with a really precise idea of who the audience is and what they will want from a very specific sort of game, even if that means the chances of netting a truly huge fanbase can go whistle. I sensed a bit of the this mindset when I recently loaded up Elite: Dangerous, a game that is going to befuddle and repel as many people as it delights, and is all the stronger for it. And I felt it very strongly with Spintires, an unlikely Steam bestseller about getting battered old Soviet trucks out of mud.

Wonderfully, this is what a bestseller looks like in 2014.

Maybe this is the palatable future of the exclusive, or the real lesson, at least. So many games get made these days, and so many different people play games and for so many different reasons, that developers can increasingly all but do a spiritual exclusive anyway: they can tailor their game for a tightly defined section of the wider audience, and hopefully balance the books so that they can make money out of it that way too. The Spintires developers weren't locking the rest of the world out when they made their game, but they were allowing themselves to forget that the part of the world that doesn't really care about battered old Soviet trucks exists.

Spintires, and the games like it, are almost the non-awful version of Mentions, then - a reminder that a more connected world can also be one that's simultaneously more fragmented. Best of all, though, with a spiritual exclusive you have the chance - via a Steam sale or a demo or even a few minutes of bored browsing when you're in the mood to take a punt - to find out that you might actually fit quite nicely into a niche demographic that you'd never even been aware of after all. And you won't have to hang out with William Shatner to do it.

Although, granted, he seems nice.