in my experience its usually the adsl companies that cap users for heavy downloading, i've seen download rates go way down after heavy usage on certain isp's. I'm on telewest and you might pay through your teeth to get a fast connection but I've been using bittorrent ever since I got broadband (nearly 1.5 yrs) and pretty much used it constantly with dling and uploading and never ever got a warning or got capped. I guess it depends on what you download eh?