A pretty morbid topic, but I would either have "Take my life. Please." or "The guy next to me smells."
Perhaps "If you're standing in front of this gravestone to read this, get off my body."
"See you in hell, suckers."
"On the third day I rose again. Stupid grave robbers."
"Shoot, I guess I didn't discover immortality."
"Behind you."
Or more seriously:
"Rest in pieces"
Colin Clark
Ally of Madness
1997 AD - 560 BC
Okay that really wasn't that serious.