In case you aren't aware, BTsearch.net took it upon themselves to have a crappy program which rips all the links off of 400 different websites (including this one). The problem is everyone who downloads this search tool and clicks update database is using your site's bandwidth, EVERY time they click update (even if they don't ever use your site).
Unless you want 10,000 extra hits a day and have bandwidth to spare, you should block anything soming from there (referrer is btsearch.net)
While maybe useful for not having to check 5 sites to find your fav torrent, this is destroying smaller BT sites that now only display "503 Bandwidth exceeded"
Don't bother asking them to leave your site off their list because it is a 'submit torrent site' link based (and they are tools).