This is probably the best puzzle/logic game that I have ever seen. It is composed of 25 levels in which you need to pass certain tasks to reach the next level. It is written in a story mode which makes it more enticing. Many of the puzzles I have heard before however it only takes not knowing one answer for you to become stuck. Adobe Flash is required to play at the following link.
Prove your logic website: http://www.games68.com/games.php?id=2169533