http://www.makeuseof.com/tag/5-free-act ... s-windows/
including: MechWarrior 4: Mercenaries
Its been released for free by Mektek http://www.mektek.net/projects/mw4/index.html . They got permission from Microsoft to release it for free including the Inner Sphere Mech Pack and their own Mekpak.
and Full Spectrum Warrior http://news.bigdownload.com/2008/10/07/ ... free-game/