If you have lot of time to spare, then you can start participating in contests offered by various sites. It's obviously likely that you won't win all of the contests, but the more you participate, the better your odds. Little things do start earning up and besides money, you can possibly win things like movie tickets, sample products, gift coupons, etc.
Where do I look for contests?
* Browse through the net and make a list of sites which offer contests
* Get registered in those sites and check for new contests daily
* Participate in as many contests as possible
* Browse through the search engines regularly and look for any new contests What do I gain by participating in contests?
* You can win cash as well as other perks like gift cards, coupons, and trips.