All or Nothing - Competitive donations for causes you care about.
Involve - Get behind-the-scenes access to your favorite nonprofits
Creddon - Tweet for a cause and a sponsor will donate $1 to charity
Klava Fund - Crowd funding for personal matters or grand causes
The Groundwork Donations - Seamlessly collect donations on your website
Public Design Vault - 500+ design tools for public good, all in one place