Mac Plus emulator for iPhone
If you were waiting for a reason to jailbreak your iPhone, this might be exactly that moment you have been waiting for. Mini vMac is a complete emulator of the classic Mac Plus for the iPhone, admitted rather useless but oh so nerdy!
Named Fork ported this originally Mac OS X app to the iPhone. Because of restrictions in the iPhone OS, the jailbreak is required. Mini vMac is free and available via Cydia.
The Mini vMac app emulates the Mac Plus hardware, but you will need to provide your own OS. Once the original OS is installed you can play classic games (which you also need to own or you could find them somewhere online)