cheatproxy is a HTTP proxy which intercepts communication with BitTorrent trackers and modifies the amount of data uploaded. By default it listens on localhost:8000 so it should simply be a case of running cheatproxy and configuring your BitTorrent client accordingly. cheatproxy uses a file to map BitTorrent trackers to a number which the amount of uploaded data will be multiplied by. By default cheatproxy will look for a file called "trackers" in the current directory but you can use the -f command option to specify an alternative. The "default" mapping will be used when no other is applicable. cheatproxy comes with a sample file called, unsurprisingly, "trackers" which illustrates the syntax.