Microsoft's free set of multimedia add-ons for Windows XP. Windows Media Bonus Pack includes: Plus!

MP3 Audio Converter LE - a free component of the program Plus! The Windows Media Player toolkit (e.g. MPXP Tray Control, Playlist Import to Excel utility, Media Library Metadata Update Wizard), Windows Movie Maker Creativity Kit - a set of sound effects, music, images and video files to help you create movies in Windows Movie Maker, as well as complexion and visualizations for Windows Media Player.