Free Patterns From Pattern8
Pattern8 is a website that presents beautiful & free repeating patterns.
A nice feature is the ability of sorting patterns by color that helps finding a pattern that will fit the overall of the design.
There are currently 90+ patterns & new ones are added frequently.
P.S. Pattern8 is a fork of PatternHead, a website that offers free vector and pixel patterns but with a wider content. It is also a place to find vector formats of the most patterns in Pattern8.