Remember awhile ago when someone said something about MechWarrior 4 being free someday?
That day is apparently now.
According to the website, the download contains MechWarrior4: Mercenaries, and both the Clan and IS mech packs. I have no idea of it includes the original game or not.
I never bought the mech packs or mercenaries, so yeah...I'm downloading.
It should be noted that you have to install the MekTek X installer to install the game for you. It seems to be downloading a la torrent, so don't expect a fast download.
But hey...free MechWarrior, so you can't complain too much.