Provides an easy, instantly accessible method of determining if you are behind a proxy..
For those who want to be instantly assured that they are still browsing through a VPN or behind a proxy, proxycheck stores a list of "safe" external ip addresses and alerts you if at any point an IP not in this list is visible to the outside world when you browse.
update 1.2: Upgraded to work with new versions of Chrome.
Coming soon: speed and ui improvements, plus the ability to select your own ip service!