The king of the Marvel Cinematic Universe isn't in superhero movie mode at the moment. He's out promoting his new film The Judge, and as part of that promotional tour he took some time today to head to Reddit for another installment of that site's popular "Ask Me Anything" feature. Fans asked him about The Judge, his favorite pizza toppings, whether he prefers dogs or cats, his music career and plenty of other things, but, of course, the event couldn't pass without some nerdy talk, so there was also plenty of chatting about Marvel Studios, the future of the Sherlock Holmes franchise and more.

The whole AMA is definitely worth reading if you're a Downey fan, but if you just want the geeky highlights, we've gathered them all below.

On his awesome facial hair:

When asked how he got his always-perfectly-groomed facial hair, Downey brought up memories of his first Marvel appearance in Iron Man.

It started with the first Iron Man: a guy named Pedro from Shave of Beverly Hills. I mean, this guy's an artist. He's like the Edward Scissorhands of Mustaches and Beards. And then, once you set a standard, it's all about upkeep and modulating it. It tends to be a lot of work, but I'm glad you appreciate it.

On Sherlock Holmes 3:

When asked about a continuation of the mystery adventure franchise he stars in with Jude Law, Downey confirmed development, and added that he's also working on another classic crime fiction property.

Yes, we have a Sherlock 3 in development. We want it to be the best of the series, so that's a pretty tall order. Also,Perry Mason is a property I'm looking forward to developing further, going back to the 1931 book series...similarly to what we did with the first 2 Sherlocks, mining the original material for things that are "new."

On his favorite superhero:

When asked who his favorite hero is, Downey deferred to his child, whose favorite superhero is not Iron Man.

My 2 year old is fond of Hawkeye, so just for today, he'll top my list.

On an appearance on Agents of S.H.I.E.L.D.:

When asked if he'd ever show up on Marvel Studios' first small-screen venture, Downey was very open-minded.

Nothing is impossible. But there might be a fair amount of red tape involved in something like that. I love Clark Gregg, and am pleased the show is doing so well.

Later, when asked what show he'd most like to cameo on, the series came up again.

Agents of S.H.I.E.L.D.

On Mel Gibson directing Iron Man 4.

When asked about a remark he'd made suggesting he wanted longtime friend Mel Gibson to helm his return as Iron Man, Downey both played down that quote and teased the future of Marvel.

It was an offhanded remark to a journalist and friend. I have other projects in mind for Mel and I - sooner than later the Marvel Roster will be made public and all questions will be answered.

On dealing with the Tony Stark persona:

When asked how he deals with being tied so much to Tony Stark in the public eye -- to the point that people sometimes think he's just playing himself -- Downey talked about the importance of remembering when he's pretending and when he's not.

The first Iron Man was essentially wrapping the character around a cooler version of "me." As we've gone along, I'm starting to wonder who's playing who, and I'm glad there are so many talented new people in the Marvel lineup. Ultimately, I'm real, and he's not. It's kind of important for me to remember that.

On his favorite fan encounters:

When asked about his favorite meetings with Marvel lovers, Downey said it all comes back to the kids who dig superheroes.

I love running into kids who didn't expect to see me. I once ran into a four year old who just happened to be wearing a Captain America mask at the time. It seemed natural to him, being that he was Cap, to see some of his friends around. I think I was more excited than him.

On another possible TV cameo:

Downey was also asked about, of all things, Doctor Who, and hinted that he wouldn't be opposed to visiting that series.

It's funny you'd bring that up. A writer asked me to watch a particular episode about a month ago, in hopes of helping us break story on a project. An incredible series. Anything's possible.

(Via Reddit)