Here is a new bundle set from GamersGate:
Countdown Bundles

This new bundle set contains five separate bundles, one for each week and each for 4$. With each bundle you get a 1$ off the next one so if you get 4 bundles the last one would be free. Also there is a charity involved as usual for these bundles. Nearly all these games are either on Steam or on Steam Greenlight. So you'll get Steam keys for the ones already in and also for those who pass the Greenlight trial. All of the games will be on GamersGate too but voting for them on Greenlight would certainly help.
There is also bonus content if they pass a certain sale amount but the amount isn't clear yet. The content would be 7 games and 6 OST.

Two points before the list:

1. It's 10$ for 20 games.
2. The last one is basically free if you got the rest.

Here is the full list:

Week 1:
Aeon Command (Greenlight)
Genetrive 2
Space Pirates and Zombies (STEAM)
Waveform (STEAM)


Week 2:
Caster (STEAM)
Hegemony Gold: Wars of Ancient Greece (STEAM)
Strategic War in Europe (Greenlight)
Zombies (Greenlight)


Week 3:
Alien Hallway (STEAM)
Bridge It (Greenlight)
Eryi's Action (Greenlight)
Terrorhedron


Week 4:
Achron (STEAM)
Alien Shooter 2 Conscription (STEAM)
Orczz (Greenlight)
Syder Arcade (Greenlight)


Week 5
War of the Human Tanks (Greenlight)
Will Fight for Food (Greenlight)
Zafehouse: Diaries (Greenlight)
Zombie Shooter 2 (STEAM)

The first week is already on.

Since the keys are mostly Steam I'd assume the usual key exchange will work.
Updates will follow, and feel free to post here about these games they need reviews.

It is week 2 now.
Also there is a list of Unlocks now.

Two steam keys this week and 2 Greenlights.