The creators of Commodore 64, that emulator app that eventually gained Apple's blessing, emailed to say that they have released a brand new version [iTunes link] with some brand new (old) C64 games to revisit. The gist of this one is that you can buy C64 ROMs to play through in-app purchases, but right out of the gate with version 1.2, three different games are free: Bruce Lee, Laser Squad, and Samurai Warrior. So if any of those ring your nostalgic bell, you can go jump in on the app now -- it's $1.99.
If you want to add in some extra games, it'll cost you 99 cents each, but they've now made Alleykat, Uridium, Paradroid, Stormlord and Nebulus all available that way. Unfortunately, not all emulator developers have been able to secure such a deal with Apple, but C64 enthusiasts have to be excited about what's available with this one.