Jet Set Willy originally came out in late 1983 for the ZX Spectrum, and was a development of an earlier Spectrum game called "Manic Miner", itself an adaptation of a game for the Atari called "Miner 2049'er". To a generation of computer users, it's an undeniable classic.
This game was a huge success for ZX Spectrum, because of this the unit started to sell more and that was the start of home gaming as we know it. The game got me hooked back then, while by today's standards it's somewhat primitive and ridiculously simple to play, it still manages to amuse, delight and frustrate me years on.
I wouldnt say it was the Most Under-appreciated Game, but I think some younger people today dont appreciate how they got there X-Box/Game Cube/PlayStation 1 or 2, if classic games like this had not been created there would have not been a home console market like there is today.
Im getting old?