And as of lately, GTA San Andreas and Soulstorm.

Here's are a few outstanding flash games that are just awesome to waste time with:
Action / turn based fighting: Sonny 1 & 2 (yeah Phobos, not just 2)
Mastermind, World Conqueror a funny and well made strategy game, although not very challenging.
Gemcraft and Protector III (almost more RPG than TD) are my recommendation for TD lovers.
Monsters Den: Book of dread is a very in-depth and long-lasting (for a flash game) dungeon RPG.

As you might notice they are all on Kongregate. IMO the website with the best quality flash games. Have fun.

I played Sonny 1, beat it and started Sonny 2 :C It is just that Sonny 1 is so not customizable D:

Heroes of Newerth and occasionally Starcraft.
If I'm too bored to play either I watch videos on YouTube.

Yeah it was a nice touch that they added some limited control over your teammates it made a great game even better. But I somehow liked the setup, story, sequences and all that a little better in Sonny 1, so I view them to be pretty equal.

I do agree, Sonny 1 made more sense than Sonny 2, in many ways. I lol'd at Greg in that weird cave anyhow.