(via this thread
It appears Steam is upset about the bad press from 3rd party DRM so they've closed down all the old DRM list threads. Fortunately someone is hosting a list on an external server now.
Crysis 2 DRM summary from steamdrm.flibitijibibo.com
Account Based DRM:
-Crysis 2; Online play requires a MyCrysis account
Solidshield is Tages’ new DRM technology. It is presumed that this is their replacement for TAGES:
-Crysis 2; 5 machine limit