After playing "Portal" (the computer puzzle game recommended by Eric) and finally beating it, I was left slobbering for a new computer puzzle game to play. What filled the void was not a new game, but an old one.
Yes, "The Incredible Machine", is a shareware program from the 1980's, but it is one of the most entertaining puzzle games I have ever played. I play it again every few years when I forget how I first beat it, and it is always just as fun. I know that I have told all of you about it before, but for those of you who have never played it, I wanted to let you know that you can download it for free at ( www.bestoldgames.net/eng/old-games/the-incredible-machine.php
) . IF you beat the first 20 or so puzzles and still want more, you can purchase the rest of the game. There is also an "Even More Incredible Machiens" game for those who still can't get enough.
The program is in dos, so when you start it, your windows screen goes black of just a second before the game boots. It is definately old school, but it is also definately fun. Just thought I would let you all know about this really cool game once again.