Mac OS X - where to find Chrome and Firefox temporary files?
Firefox stores its files in /Users/username/Library/Caches/Firefox/
.
Chrome stores its files in /Users/username/Library/Caches/Google/Chrome/
and (very short-term) in /private/var/folders/
.
You can see these paths when you run either of the following:
sudo fs_usage -f pathname Google\ Chrome
sudo fs_usage -f pathname firefox-bin
If you just want to download FLV files off a video sharing site, I suggest using a browser plugin, or Safari's Web Inspector with resource tracking.