Any of you that have an older "fat" PS3,
DO NOT TURN IT ON.
Apparently someone at Sony doesn't know how to create a calendar that successfully deals with the month of February. At midnight GMT all "fat" PS3s began showing the 8001050F hardware error (including mine) accompanied by "An error has occurred. You have been signed out of PlayStation Network (8001050F)", "The current date and time could not be obtained. (8001050F)", or "Failed to install trophies. Please exit your game." The issue has been reported on consoles that are not connected to the internet, so it's definitely a firmware problem.
Some people have reported that the date has been set back to 1/1/2000, although I didn't see this on mine.
Being unable to connect to PSN is bad enough, but it's also affecting the functionality of downloaded games and content (Entroper and I couldn't play any downloaded Rockband tracks and our imported Rockband 1 tracks didn't even show up), as well as disc-based games that only go online for trophy information. In particular, it's been reported that Heavy Rain won't even load, just reboot your system.
Sony says they hope to have this fixed within the next 24 hours, and warn "fat" owners not to turn on their systems to prevent data loss and corruption. "Slim" owners are not affected.