Amongst the games is the crazy Linux Tycoon in which you can roll your own OS:
And other such niche titles, but there seem to be some good tools in the deal too.
IHMO this seems to be rather an experiment, and the guy is promising to refund the money if he doesn't reach the goal of US $4000 by today (Yeah I said we are late, and I have no good excuse as it was posted a few days ago in our forums :-/ ).
So far he has gotten a bit more then half of it, so maybe it's still possible to reach the goal. However I guess the time was just a bit too short, and the games offered also a bit too not mainstream for this to really have a chance.
Edit: He extended the deadline until Friday, as the goal is almost reached.