Extended Module Player. GPL. OS Independent.

freshmeat.net: "The Extended Module Player is a command-line mod player for Unix-like systems that plays over 80 mainstream and obscure module formats from Amiga, Atari, Acorn, Apple IIgs, and PC, including Protracker (MOD), Scream Tracker 3 (S3M), Fast Tracker II (XM), and Impulse Tracker (IT) files."