Torrent2exe is a pretty amazing web utility that turns .torrent files into .exe files that are self contained BitTorrent downloaders. This allows you to download bittorrent files without having to have a BitTorrent client installed on your computer.
It is really easy to use too, all you do is download the .torrent file from whatever site you get it from, upload the .torrent file to torrent2exe.com, click the download button and you are off and running with an executable file. When that executable is ran it opens up a download window and starts to download the source file to the directory that the .exe is located in.
If you want to skip a couple of steps you have the option of entering the URL to the .torrent file.
This looks like a really good way of getting your friends into BitTorrent that have had some trouble wrapping their heads around the idea of it.