Quirky bills itself as a "social product development" site which means that they produce new inventions in a fun new way.
Basically, Quirky works like this: Someone, let's call him "Theodore," pitches an idea to Quirky. It costs him 10 dollars. The idea is then put up against all the other submissions to be voted on by the community. The winning idea goes through several stages of development, all of which are voted on and influenced by the community. Eventually, if all goes well, the product is released and Theodore collects royalties. The entire process could probably take up to a year before Theodore ever sees anything for his invention.
But most people on Quirky don't actually submit ideas, they just influence them. Which can also potentially make you some money. Every time you voted on a product or provide some idea, you can earn "influence." This influence translates to a share, albeit microscopic, in the profits from the invention.
I've been on Quirky for a few months now and influenced a number of products. But, I haven't actually made any money although the cheering little "potential earnings" meter keeps steadily rising. The issue is that once the product is released, it goes into "pre-sale" made until a certain number of orders are made, stalling the process even further.
There are people on Quirky who have supposedly made hundreds, even thousands, through influence alone but... let's just say they are the minority.
Overall, Quirky is fun and probably not much else. You won't get rich off it but the process and the products are enjoyable and interested. I recommend it to pass some time, not to make any money.