I was using DropBox for a while (albeit on someone else's account) and it works/worked well. Initial link wasn't immediate, but certainly faster than FTP or any other method I've used before.
Never looked into how it works, but it seems/seemed to populate the other machines at something like one-and-a-half times the 'normal' web download speed - although this is user "feel" rather than any timed test.
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I've seen the light... It was green, flashy and attached to a Network Interface Card...
Whenever someone says "You can't miss it" I invariably do...