RatioMaster is software designed for spoofing downloads and/or uploads on BitTorrent trackers. It's useful for artificially increasing your ratio on BitTorrent trackers that keep your global ratio (aka private trackers). It is able to emulate a lot of current clients and is extendable by simple ".client" files that contain everything needed to emulate a new client.
Version 1.5 brings lots of new stuff, like the ability to set minimal and maximal speeds for spoofing torrents and the ability to stop an operation after a certain condition is reached (either operation time or data spoofed).
RatioMaster is written by the people over at http://www.moofdev.org/ - feel free to poke around, maybe check out the forums - http://www.moofdev.org/forums/