Force-Reload-for-Chrome is a project mainly written in JavaScript, it's free.
Simple Chrome extension to force Chrome to request uncached versions of specified resources
Requires experimental extension API support (steps 1 and 4): http://code.google.com/chrome/extensions/experimental.html Install as an unpacked extension: See step 4 here: http://code.google.com/chrome/extensions/getstarted.html
patterns.txt gets regular expressions, one per line (no / / delimiters), e.g. :
www.google.com
If a request URL matches the regular expression, we remove the If-Modified-Since and If-Unmodified-Since headers and set Cache-Control: no-cache and Pragma: no-cache
Tested and works in Chrome 14.0.835.29 dev