Wrapster is an archiver designed for peer-to-peer file sharing. Like WinZip and tar, it creates archives that can contain more than one file. But Wrapster's difference is that its file format is designed to mimic an MPEG audio file of type .mp3, making it especially good for making your free software available on music-sharing services such as Scour or Napster. Because Wrapster uses no compression, it's standard practice to use another archiver to create a zip file and then putting that file into your Wrapster archive along with a README file.