Now that Steam has Free 2 Play games in the store, I wanted to try some of them to see if they are any good. I am currently playing Spiral Knights and I'm having a great time. Have any of you guys been playing any free games on Steam? Wich is your favorite?  
 
Also, if anyone likes Spiral Knights... care to explain to me how the whole mineral system works. I kinda don't get it I mean. I just went into my first 4 lvls (depths) of some gate and don't know how to unlock others... I read the tutorial but the game is still very complex.

Spiral Knights is good. It's the only one I can play on Mac.

It's cool that they're there, but none of them have interested me and I'm too busy replaying KOTOR/inFamous, playing SC2 MP, and Frozen Synapse. Maybe I'll check them out later if I'm bored but I doubt it.

Spiral Knights is good. It's the only one I can play on Mac.

Regardless of what any of us think of it, it's going to be very successful thanks to our wives, girlfriends and mothers. I personally think Valve are evil geniuses, if they get a cut of the money on these microtransactions then it has the potential to make more money than any of us realise. It also gives them the opportunity to advertise and push other F2P games on people who typically pick their game and stick with it.

Of course I'm gonna give them a go, because I'm unemployed at the moment and I've got all this spare time lying around.

I hope that stuff like League of Legends and LoTRO will be on there, would be fun to try them out and Steam would make the whole process super simple. Also, this is makes me think whether, as Patrick said, TF2 will become free and also whether DOTA2 might be free as well. 
 
Two of the games on there right now are MMORPG's so I don't know whether I'll have the time to check those out. Spiral Knights seems pretty good though.