We actually launched a very similar website with the same goal earlier this year which is cool because it validates our idea. Works almost the same way! http://zombal.com/
Interesting. A lot of the "challenges" here: http://zombal.com/scientific-challenges seem like generic questions rather than requests for specific technical work/lab experiments (e.g. "Is dieting an ineffective way to lose weight?")
Is that a design choice? Is there as much overlap as you think between your site and the one mentioned in the original post?
We actually have two formats, one is called Standard Zombs (standard tasks) which is bid-based just like ScienceExchange. The other is called Bounty Zombs (Q&A's) similar to http://prizes.org/ format. If you go to http://zombal.com/scientific-challenges as you pointed out you can filter out the different types.
