Once of the biggest allures in life is scarcity, as we all want what we can't get. In the extremely competitive world of credit cards, there have been banks that have gone a bit too far, and offered products with rewards that were so generous as to be unsustainable. In other cases, there have been some great credit card offers that never quite gained traction and were pulled from the market.

Here are four of the best credit cards that you can't get, as well as some pretty good alternatives.

Charles Schwab Bank Visa

In December of 2008, the Charles Schwab investing company introduced a credit card with an unprecedented rate of return. Cardholders receive 2% cash back on all purchases with no annual fee and no foreign transaction fees. Despite, or perhaps because of, its popularity, the card stopped accepting new applicants in early 2010.

But thankfully, there isn't much need to mourn its loss. Last year, Citi introduced its Double Cash card that offers the same rate of return. Cardholders receive 2% cash back on all purchases; 1% cash back at the time of the transaction, and another 1% back when payment is made. In addition, new applicants also receive 15 months of 0% APR financing on both new purchases and balance transfers, with a 3% balance transfer fee. There is no annual fee for this card, but there is a 3% foreign transaction fee.

Old Blue from American Express

There is a card called Blue from American Express that is currently offered, but it's a rather ordinary card that offers one point per dollar spent, and not much else. However, there used to be an extraordinary card offered by the same name, that some now refer to as "Old Blue." This previous card offered 1% cash back on all purchases, until cardholders reached $6,500 in annual spending. After that, cardholders then received an amazing 5% cash back at U.S. supermarkets, gas stations and some drugstores. At those rates of return, credit card rewards experts became very enthusiastic about using their card to earn as much cash back as possible, and American Express later limited the 5% rewards to cardholders' first $50,000 spent in a year. Nevertheless, legend has it that you may still be able to apply for the Old Blue card if you know where to look. Instead, American Express offers its Blue Cash Preferred, which offers 6% cash back on up to $6,000 spent each year at U.S. grocery stores. There is a $75 annual fee for this card.

United Airlines MileagePlus Presidential Plus Card from Chase

Aside from being the only card that has the word Plus appear twice in its name, this card had a lot of things going for it. Cardholders receive access to the United Club and Star Alliance airport lounges, and receive their first and second bags checked for free for themselves and one other traveling companion. Customers also receive Premier Access travel services, which include priority check-in, security lanes (where available), boarding and baggage handling. But what really sets this card apart is the ability to earn 1,000 Premier Qualifying Miles (PQMs) for each $5,000 spent, allowing cardholders to earn elite status much more quickly.

But because this card was originally offered as a Continental Airlines card, a company that has since been acquired by United, this card is not available to new applicants, although existing cardholders continue to enjoy its benefits. As an alternative, new applicants can apply for the United Club card from Chase, which offers many of the same benefits, but no PQMs. There is a $395 annual fee for the United Club card.

JP Morgan Select from Chase

This was a very high-end card, but with an affordable price tag. Cardholders earned double points on many travel expenses, and one point per dollar spent elsewhere. It was also one of the first cards offered in the United States with an EMV smart chip. Other benefits include all sorts of travel insurance and purchase protection policies, as well as no foreign transaction fees. There was a $95 annual fee for this card.

In retrospect, it's obvious why this card is no longer offered, as Chase's current Sapphire Preferred card now has almost identical terms — including double rewards for travel purchases, the $95 annual fee and no foreign transaction fees.

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