I have found that online flash games are extremely popular. This is probably because you (usually) don’t have to wait a long time to download it and they are free. Unfortunately because they are free they usually aren’t good/playable and they aren’t updated often/ever. But there are some that stand out. I am here to tell you in no particular order what those games are.
1. Dwarfs Complete
http://lineage2.plaync.jp/l2fun/flashGame.aspx

This addicting puzzle game is very nice for several reasons. It automatically saves your progress (using cookies i guess). It’s not too hard but there is a level of mind power that is required to solve the various puzzles. The site is in Japanese but just ignore it and play the game. The game itself is about a dwarf who I think is trying to get off of either an abandoned planet or the moon. To complete the game you need to find 40 pieces of equipment create a floating rock and activate the spaceship to get off the moon/planet. You control your character with the arrow keys and you can use various tools you make from materials by clicking on them. I really liked this game and I recommend it to people who like puzzle games.