There's been some interesting events in the P2P world recently.
On the 8th of December it was announced that uTorrent (probably the best bittorrent client around for windows, although closed source) had been bought by BitTorrent Inc. As a direct result of uTorrent being bought over and in the hands of the "enemy" (RIAA, MPAA etc), a lot of trackers are banning the use of uTorrent. This means that if you want to download anything off that tracker, you now cannot use uTorrent. One of the highly recommend options is Azureus, which as good as it may be, is also extremely bloated. Whereas uTorrent can download away with as little as 2 megs of ram, Azureus demands a minimum of 50 megs these days.
Personally, i think that this is a bit over the top. Banning the best client i've ever used simply because it has a new owner, BitTorrent inc, is a bit over the top. It's always possible that this decision will be changed in the future, but the odds are slim. Farewell to the best client ever.