IPRIVO client is open-source based (openVPN).
Supported operating systems: Windows 7 (32+64bit), Vista (32+64bit), 2008, 2003, 2000, XP.
Triple-DES encryption of all communication.
ALL communication on all protocols (TCP, UDP, etc) is passed through IPRIVO servers, including DNS requests.
Client access logs are anonymized (don't store real IPs) and are discarded after 1 week.