Peggle does indeed run in offline mode on Steam, both on my desktop and my laptop. I suspect the reason Belcaw ran into problems is that he played his copy on a different machine previously. The way Steam's offline mode works is simple. Playing the game on a machine while online (you have to be online to download it in the first place) authenticates it for that machine. You can then play the came in offline mode indefinately until you login to your Steam account and play the game on a different machine. Only the most recent machine the game was played on is authenticated for offline mode play. This is actually a rather elegent, and usually invisible precaution. I still prefer Stardock's stance on DRM, but Steam has the only DRM that doesn't piss me off. Period.