Megadrive Mercs is bloody awesome.
Here are a few that spring to mind:
Tempest 2000, Missile Command 3D, Breakout 2000, Defender 2000 - Atari Jaguar
You get the arcade original as well as an enhanced version and a totally new up to date version of the game.
Rampage, Xenophobe, Qix, Double Dragon, Rampart, Battlezone 2000 - Atari Lynx
All feature enhancements over the arcade game, in the case of the last one it also has an enhanced version.
Video Olympics, Space War, Combat, Outlaw, Air Sea Battle, Space Invaders - Atari 2600
All feature extra game modes that were not in the even more simple arcade originals.