I beat ME1, played a bit of 2 but never finished it. Never saw what made these games special though.
Lokarin posted...ehhh, I thing SpaceChem is the last 'new' puzzle game I played that I liked.
You should really check out Zachtronics' other games. Inifinifactory and Opus Magnum are similar to Spacechem. TIS-100, Shenzhen I/O and Exopunks are all programming themed puzzle games, but still awesome.
TIS-100 is older than Spacechem, the rest was released afterwards.