beHidden.com - Offer 30mb of free anonymous transfer per day. Paid service available with no limits. Also offer anonymous email.
CECID - Uses a client called FLACCID to remove tracable information via a decentralized P2P anonymity network.
CGI Web Proxy - Paid full service and free limited service offering web surfing via CGI proxy using SSL.
CryptoTunnel - Offers windows software to secure internet access via an internal SOCKS proxy. Can be used with SOCKS compatible programs.
Goldens.com - OpenVPN based secure proxy service based in the Netherlands.
Great Firewall of China - Provides a tool to see if a domain name is censored in china and allows you to view the domain via a Chinese proxy server.
Relakks - PPTP based VPN service based out of Sweden. The site claims their Swedish jurisdiction allows for greater protection from government subpoena.
Somebody Anonymizer - Commercial service provides proxy, enhanced DNS, privacy protection, anonymous surfing, anonymous mailing and anti-censorship services.
the-Cloak - Anonymizing proxy with option to remove Java, JavaScript, and block cookies and ads. Requires JavaScript. Pay service offers more bandwidth than free version.