Shutterstock.com

Sell your pictures !
You can upload your stock photos on this website and earn whenever someone downloads your images. It does add up over the time.
After registering you need to upload 5 images. They will review and approve your images. After which you can keep uploading as many pictures as you can.
Images should fit their requirements in terms of resolution, clarity etc.
You can use the following link to sign up as my referral.
Submit Photos to Shutterstock and make $$$!

Or use this link.

http://submit.shutterstock.com/