There was a game similar to this posted earlier on the portal. I said this about that one nad I'll say it about this one too - it's way ahead of it's time. I had a ton of fun playing this, as the concept still feels fresh 20 years later somehow, and the levels are neatly designed. In addition the little text portions between levels did a good job guiding you through the game.
I'm happy to say this game was not only finished, but was followed up by several other games as well.