AMP is a command line mp3 player/decoder released under a BSD style license. This became the foundation of WinAmp. Winamp is 'the' mp3/audio player for Windows, and is said to no longer contain any remnants AMP source these days.

Some time after Winamp was released, it was cloned as 'x11amp' for *nix - which was again based on AMP. Winamp later got the x11amp folks to rename their player, and so it became 'xmms' (X MultiMedia System).

AMP is also the tla for the Active Measurement Project, run by the NLANR Research team in the US. It consists of well over 100 well connected "amplets" spread over US universities and research organisations. All amplets ping each other in a full mesh once per min, and traceroute between each other once per 10 min. All results are collected on a central server and displayed to the public. Go here if you want to know more or see the results. This project is lead by the head of the WAND group at WaikatoUniversity and as such, many students in this group have had something to do with AMP at one point or another. This is another example of NamespaceCollision.