FunkyCache is an extension that really clears the cache.
I took a look at the souce code of another cache extension and realized that it didn't actually clear all the cache.
So I figured I would make my own, that won't take much space on the toolbar either.
· Thunderbird 1.0 - 1.6 ALL
It should appear under your tools menu option (under name FunkyCache).
Add FF2.0 support:
Unzip funkycache.xpi file, then You just need to change the em:maxVersion tag content in install.rdf under the comment to:
Rezip funkycache.xpi, install it and you're done it works under Firefox 2.0.