Those are some great ideas!

So what's stopping another developer from going through these and stealing the ideas for themselves? I know that an idea doesn't on its own make a great game, but it would prevent double fine from using it again in the future.

He also said that he's going to shove his sausage in our faces :-/

I guess nothing would stop them, as ideas are not protected, but because of that it also wouldn't prevent DF from using the same idea nevertheless, and maybe their version of the game would be superior. Then again, some of their ideas don't sound that original either (e.g. physics-based puzzle platformer with a flexible Blob of Goo times two).

Open wide!

yea I'm wondering about this also. I mean are they gonna sell these prototype on steam after? are they gonna finish it and than sell it on steam at some point and we will get the keys for those finished version? Steam doesn't sell prototypes do they?

Putting the 4 prototype aside, what about Costume Quest? Is this prototype version of it different from the one selling $15 on steam? or is the steam version actually a released prototype in the first place?

When you buy it, you get a Steam key right away for the prototypes of Happy Song and Costume Quest, despite the fact that the prototypes aren't sold on Steam. I assume they will also add a key for the winning prototypes.
It's VERY different. It's an early version of the game, which was used to pitch the full version of the game. You can see elements of the final design in there, but it's a lot rougher. Fully playable, but not exactly a full game.
It's also a chance to vote on what you want to see from Double Fine next. Last Amnesia Fortnight, all four prototypes that were developed ended up turned into full games (Costume Quest, Stacking, Trenched/Iron Brigade and Sesame Street). So the games that win here will likely become full downloadable releases down the line.

Thanks for the clarifications, yea thought it was strange for steam to host so many prototypes from them.

I don't play full indie games that I buy 90% of the time, let alone prototypes.

you poor misguided soul - where ever is the element of begging coming into it? I think it is a brilliant stunt for PR and support charity (real charity, though you can chose not if you want)

I haven't had a chance to vote yet, but it seems like at this point the frontrunners have a lot of momentum.

Tim should take up an acting career part-time, he's pretty good in front of the camera :)

Except for the satanic ritual and the shouts at the end of that promo video, that's just too silly. ;) But I agree that it probably stood out because the rest was so flawless and funny.

Happy Song and Costume Quest prototypes are on steam already. The other 4 will be there when they are made, so you get all 6 in your steam library for the rest of eternity. I guess Valve <3 Double Fine (as we all do)