I'm sure it's already been mentioned here, but Chuck's Challenge 3D
has about 40 hour left to go, and is a little over $1,000 away from it's goal.
If you're a fan of the original Chip's Challenge (or similar top-down puzzle games). Chuck's Challenge 3D is the direct successor to Chip's Challenge (they weren't able to reuse the name), and is a nicer looking PC/Mac remake of the original iOS game, Chuck's Challenge. I don't know whether this version will include new sets of levels from the creators (both games allow for user-created levels, however), and Linux support is unlikely due to technical reasons (specifically, Unity 3D).
The minimum for securing a copy of the game is $5, half of what the price of the game will be on release. Originally, they considered giving either the full game or $10 worth of in-game credits. They (thankfully) decided on the former, but are unable to change the reward pledge text, so you can safely ignore that part of it.
The actual method of distribution is vague. It sounds like they, unfortunately, have only considered Steam. Hopefully they get enough feedback to consider their other options.
I just know that I liked the original Chip's Challenge, and I'm looking forward to playing 100+ more levels and everything else the game has to offer. I'm really hoping to see this one get at least the $1,000 more that they need.