If you didn't know, in the Simpsons (episode BABF11, "Missionary: Impossible", season 11, 1999-2000), Homer at one point yells out "Save me, Jebus!" No one's really sure why he does, though. Could be that he was just being stupid (real unusual, there) and mis-spoke Jesus's name. It could also be a corruption of "bejeezus" as in "I'm going to beat the holy BeJebus out of you." There are a few other guesses people took, as well*.
One interesting factoid I found out is that there is a "historical" reference to the word. The ancient city of Salem was conquered by people called the Jebusites. They renamed the city to Jebus. It was later renamed to Jerusalem. Jebus was the son of Canaan, and his people, the Jebusites, were descendants of the Canaanites. Jebus, incidentally, means "he will be trodden down"**.
Now, to backtrack to the Simpsons for a moment, Homer screams this while being chased by an angry mob, if I recall correctly. It's a minor point, but I think it's amusing that he'd call out to someone who's name is about being trodden down when you're about to be trampled by an angry mob.
Now, I'm sure there's more to it - anyone want to take a look? I'm curious if anyone can find anything more about it, I'd definitely like to know more, like a definite answer of where the Simpsons got it from, and also a good answer as to how it entered into (somewhat) popular usage - was it from people quoting Homer or is there another Jebus joke out there? I'll update if I find anything else out***.
* - http://www.snpp.com/episodes/BABF11
** - http://www.script7.org/genesis_10.htm
*** - Yes, this is incredibly pointless and random, but I got curious all of a sudden and had to know more. If it's any consolation, I wasted less than 30 minutes on my quest for the answer, and I was too busy coughing to do anything serious anyways.