Cinemageddon is a great tracker if you are looking for rarer/older movies. They currently have ~25000 registered users & almost 42000 torrents. They have a bonus system witch is great for people with slow upload speeds called "credits" witch you can use to buy upload credit, VIP, or custom titles.
Irc: Server: irc.cinemageddon.org Channel: #cinemageddon
Signup URL: http://cinemageddon.org/signup.php
If you are looking for a site that indexes the less known, older & rarer movies don't hesitate to try this one out.