I use Chrome, I cannot find any cache storage options... However I have 8gb of ram on this PC so there isn't any good reason why it shouldn't be still sitting in ram (other than each 32bit process can only have 2gb addressed... but hey, we ain't talking
about that much video here... until channel9 goes 1080p HD)
In Australia we have fast internet (24mb/s) but very limited or costly downloads. It is quite a pain to download 100mb in 10sec and find that I don't want to watch the entire episode.