I'm making slow progress through this, but I'm enjoying every second.  I only just found out that you can press the L button while aiming the pistol to disrupt the lights.  It's great winding up a guard because they get totally freaked out if you keep messing with the lights, at one point a guard started going on about how he was scared and wanted to go home.

"Personnel are reminded that tomorrow is new toothbrush day"

Best Xbox game by a mile me thinks.