Instead of making a new thread every time a good flash game becomes available, I figured I would try and lump them all into one.
Copy and paste:
Name:
Description:
Difficulty:
Review:
Addiction Level:
Link:
I’ll start with the newest one I’ve been playing.
Name: Sky Storm
Description: Side scrolling pilot game. Attack air targets, bomb buildings/AA guns/airfields etc., escort friendlys. - You get the hint.
Difficulty: 5/10 (not adjustable)
Review: The controls for your aircraft are nice and smooth. Bombing missions are a blast (no pun intended). Sort of easy since you can land your plane an infinite number of times to get refueled/reloaded.
Addiction Level: 6.5/10 - You can finish the ten missions in one sitting.
Link: http://www.addictinggames.com/skystorm.html
Heres the tower game from my other thread.
Name: High School Tower Defense
Description: Tower game
Difficulty: 6/10 (Maybe it gets harder in higher levels)
Review: Played for about 40 minutes during class and had no trouble getting the hang of it. You buy and upgrade nerds (towers) which you strategically place to stop the school jocks from taking the goal post and trophy that your nerd buddies stole from them. In the beginning you re arrange the furniture to create a maze and slow down the jocks.
Addiction Level: 8/10
Link: http://www.addictinggames.com/highschooltowerdefense.html
Name: Pandemic II
Description: Create and evolve a disease in an attempt to infect the world.
Difficulty: 9/10
Review: Decent strategy game. No action involved. Gain evolution points and spend them wisely to evolve your disease in the most effective way.
Addiction Level: Good for one or two long games.
Link: http://www.addictinggames.com/pandemic2.html
Pandemic was fun, try and make sure you get those small isolated countries before anything as they are hard to crack in the late game.
I spent all the beginning points to make my disease spread easier and I got those island countries easily but my disease wasnt deadly enough by the time a vaccine was invented.
Run around. Kill zombies.
TONS of games. I think you could spend weeks upon weeks here and never get bored 
You can search games by popularity and type. I literally played on that site for 6 months straight…
It is even more fun with “points” for doing games. They serve no purpose, but it gives it a better fun factor to make yourself feel accomplished. 
http://www.kongregate.com
Escape from Camp Crystal Lake
Pretty good puzzle like game involving everyones favorite goaltender.
Kind of scary too