ECONOMICS - MONEY - Websites For Saving Money

1.Airbnb - rent out a room, apartment, house, or even a castle to travelers.
2.Coupons.com - finding deals on all sorts of products - an alternative to newspaper coupons - recently raised $200 million in new venture funding
3.Gazelle - people to sell their used electronics
4.Getaround - peer-to-peer car-sharing company - borrow or rent out cars
5.RelayRides - peer-to-peer car-sharing company - key card that can be used to access a borrowed car - generates car owners an average of $250 per month renting out a car - Boston, SF
6.Home Exchange - rent out their home and find a place to stay while traveling
7.Glyde - buying and selling media such as games, DVDs, or even iPads - You can search for an item, find the price and buy it. Once it arrives you have 48 hours to decide if you are satisfied with it. If you aren't satisfied, you don't have to pay.
8.Parkatmyhouse - peer-to-peer parking space website
9.Thredup - parents Trade in a box of your kids' clothes for a box from another family
10.HomeAway - vacation rentals Sign a rental agreement, pay a deposit, and take off
11.Groupon - group deals
12.Twitter - Amazon.com and Virgin America post special deals on Twitter
13.Woot! - one special deal per day, sells various different electronics products
14.Facebook - If you "like" certain companies you will get access to special deals posted on Facebook

http://www.forbes.com/sites/tomiogeron/2011/09/02/startups-focus-on-tools-for-saving-cash/