The oil companies have been merging and being bought out like crazy for years now. Amoco is no more, Pennzoil (at least its oil and gas arm) is gone, BP just swallowed up what remained of Vastar (née Arco). Gulf and Oryx (née Sun) have been gone for a long time now.
The double names are intermediates while the leading name is still in the phage stage; ExxonMobil, ChevronTexaco and ConocoPhillips all really mean Mobil, Texaco and Phillips are gone.
Maybe another tobacco company. I think Brown & Williamson is now history after R. J. Reynolds bought it (or something like that).
McDonalds.
We can only hope… 
I think KMART is done for…I’ve been in several stores, and they all look like they are poorly managed. Regarding FORD…I understand they are in difficulties…but the stock is going up! That usually means a turnaround is in the works…anybody shorting FORD?
I suspect that Pan-Am will be going down the tubes.
Iomega (well, they used to be “major”)
Zip and Jaz drives were unique and worth buying when they were first introduced, and they were standard or optional on a whole generation of off-the-shelf computers, but CD-R and DVD-R have made them obsolete. Zip disks now cost 30 times more per megabyte than CD-RWs. And what else does Iomega sell today? Hard drives, CD burners, floppy drives, and USB storage… nothing that they do any better than the bigger players who dominate those markets.
Already happened. Time Warner bought them. They’ve already started “rebranding” here in Charlotte.