What would happen if I ran 150mm forks in a specialized enduro frame that was meant for I think up to 130mm (2004).

Would the world end, the bike snap or not very much?

you will die in a spectacular ball of flames and float up to heaven with no teeth, or skin on you face for that matter!

Lot of recent discussion here
http://www.singletrackworld.com/forum/topic/mtb-frames-and-their-maximum-fork-length-versus-the-fork-length-you-actually-run

Not to worry.

Forks went for more than what I was willing to pay.

Interesting.

The 2002-4 Enduro was originally warrantied only to 130mm. However, many owners have added bigger forks to them – myself included.

Mine had Pikes, however I've seen Maverick DUCs and even Boxxers on them.

The good news is that the headtube junction is plenty strong. The bad news is that the chainstays are the weak point and are usually the first part of the frame to break if the forks are too long.

Having said that, mine's been fine on Pikes for four years. An old friend ran Manitou Shermans on his without issue. Several people I run into on the trails on 2002-04 Enduros seem to be using bigger forks.