What is it?
Winamp Agent - winampa.exe

What does it do?
winampa.exe? - Task bar tray icon for easy access to Winamp. If you're not familiar with what Winamp it is and always has been the greatest MP3 player on the planet. With the last bunch of releases this ranges from a basic media player all the way to a full media solution with ripping and burning all built into a single interface. Originally a "rebel" piece of software its now as commercialized and accepted as anything else out there. AOL actually even purchased it... Doesn't get much more commerical and/or accepted as that.

Virus Precautions:
You'll want to keep an eye on this google search for any known viruses. The normal location of this file is C:PROGRAM FILESWINAMPWINAMPA.EXE