Placid notes that the EFF has announced Switzerland, a tool for testing if your ISP is interfering with your Net connection (e.g. by resetting BitTorrent transfers). It's command-line only at this point. Of course the tool is FOSS, and you can contribute to it via its SourceForge project. From the announcement: "Developed by the Electronic Frontier Foundation, Switzerland is an open source software tool for testing the integrity of data communications over networks, ISPs, and firewalls. It will spot IP packets which are forged or modified between clients, inform you, and give you copies of the modified packets."