When I'm bored or have free time, I make money from online surveys. It's really easy and it's all free to sign up with.
These are the sites i use & have actually received money from:
Cashcrate is my personal favorite. I make over $400 each month from just this site. You also earn points for every dollar you make, which can be used to buy things like gift cards, ipods, etc.
*Payment Method: Check
*Minimum Payout: $10
*Minimum Age Req.: 13
Anyone from any part of the world may join, BUT the most offers are available for US members.
*Payment Method: Check or Paypal
*Minimum payout: $20
*Minimum Age Requirement: 13
Accepts Members from anywhere in the world.
SB works just like Google, but every time you search, you have a chance to win "SWAGbucks", which are virtual dollars which you can cash in for prizes or free giftcards. I usually win at least a few SB every day from doing a few searches here and there. You can also earn SWAGbucks when you shop online, trade in your old cell phone or video games, or getting "swag codes"- frequently posted on the owner's blog, facebook, and twitter pages. I've only been a member for a few weeks and I've already got $20 in free Amazon gift cards (they send them within a couple days of ordering!). The site is open to people in the USA, UK, and Canada