This project is a few years old, but it might be appropriate to cover it late since [richardg867]’s Wayback Proxy is, quite literally, timeless. It does, more-or-less, what it says as on the … ...

This tutorial will help you enable or disable Automatic Proxy Caching in Internet Explorer, so that client-side processing can be used to improve browser performance.

The two extensions effectively transform a user's browser into a proxy, allowing users in oppressive countries to connect through the extension (and the user's computer) to the Tor network.