Wumi is a sendmail milter using the py-milter. It rejects mail containing certain (configurable) attachment filenames (.exe, .pif, etc.) or containing a virus (checked by calling a single-user license command line scanner) by answering the SMTP DATA step with "554 5.7.1". This way, the mail server does not have to generate senseless bounces.
iPod shuffle Database Builder allows the iPod shuffle to be used almost like any other USB MP3 player. It rebuilds the iPod shuffle's databases based on the actual content of the iPod's file system, without restrictions regarding the directory structure or file names. No iTunes or other playlist management software needs to be used.
BeatPacker is a simple Python script that uses an M3U playlist to generate a temporary folder filled with files that can be easily transferred to a portable music player. It's designed to be used as a target for drag-and-drop, a nautilus-scripts right-click action, or similar purposes. A Windows installer is available.