The first installment and origin (no pun intended) of the Dead Space franchise is available right now for free on PC from Origin and EA.
As part of Origin's new "On the House" program, EA is giving away a PC copies of the first Dead Space. Downloading a copy of the game nets you the full game forever as long as you have Origin installed on your computer. The special can go away at any time so go download now.
EA must be doing this in gratitude for not being voted the worst company for the first time in three years. Maybe we should all be a little bit nicer to them if they're giving away free stuff when they're in a good move.
Dead Space is a great franchise even with the less than solid Dead Space 3 possibly putting a close to the series.