Well, you have a couple of options
Ftp on your computer is a decent idea only if you have a good upstream...otherwise you wont get people downloading at 5k from you. Now, about hosting AMVs online, there are numerous sites that might host for you, maybe your best one? Now the site that I run is one of those, so if your interested click the button below.
AMVs can get huge, many webhosts dont like the bandwidth use. Mine contacted me about using almost half a gig of bandwidth a day...they really dont like it. But, they do say unlimited bandwidth, and they had to hold to their contract. Be sure you find one with unlimited, otherwise your gonna be in big problems with the bill
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