BofA has a feature called ShopSafe that lets you generate virtual credit card numbers tied to your main card. They got it when they acquired MBNA/FIA Card Services. According to the Wikipedia article[1] a couple of other banks have offered similar services over the years as well (though looks like a couple have been canceled).

With ShopSafe, each virtual card has a custom expiration of 2-12 months, a max spending limit (ex: $100), and only a single merchant can bill to it. That last feature is important as it means that even if it's leaked before the shorter expiration period nothing should be able to be charged to it. Recurring charges are possible though (ie the same initial merchant can charge you again) so you can use it for situations that require recurring billing. Either way the spending limit still applies.

Anonymity aside, I'd argue that virtual credit cards are even better than BTC from a consumer's perspective as you still have the power of charge backs. Each one has the same rights as your original card including the right to declare a purchase as fraudulent (ex: the merchant didn't ship the goods).

Would be cool if someone would create a physical version of these virtual cards that gets created on the fly for each transaction. I was hoping that Coin or one of the other "virtual physical cards" would do that but I guess that'll come later.

[1]: http://en.wikipedia.org/wiki/ShopSafe