Of course, it works for me, in my very uncontrolled test: 1187016079.685 65938 192.168.1.140 TCP_MISS/200 2679416 GET http://ash-v287.ash.youtube.com/get_video?video_id=HR-JFOWpsNM - DIRECT/64.15.126.164 video/flv Then in store.log: 1187016079.682 SWAPOUT 00 00000D09 C6F49515BDA7D2CC7C82C800395B14A6 200 1187016014 1186779011 -1 video/flv 2679076/2679076 GET http://ash-v287.ash.youtube.com/get_video?video_id=HR-JFOWpsNM Ok, so it was swapped out; then I clear cache and jump back in: 1187016153.202 3249 192.168.1.140 TCP_HIT/200 2679425 GET http://ash-v287.ash.youtube.com/get_video?video_id=HR-JFOWpsNM - NONE/- video/flv Yum! (Of course there's more to caching youtube - specifically, would need to implement a patch to squid to create a URI from that youtube URL which creates the same "host" part regardless of which bit of the CDN you fetch it from - using that URL for the cache storage and lookup. That'd be a pretty nifty start.) relevant bits in my Squid config: # Cache dynamic content from youtube/etc # Let the clients favourite video site through acl youtube dstdomain .youtube.com cache allow youtube # NOW stop any other dynamic stuff being cached acl QUERY urlpath_regex cgi-bin \? cache deny QUERY refresh_pattern -i \.flv$ 10080 90% 999999 reload-into-ims maximum_object_size 32 MB maximum_object_size_in_memory 512 KB So, who wants a t-shirt for implementing the above patch and demonstrating it works with Youtube? I just don't have the time. Adrian