tyco, worldcom, qwest, global crossing, metromedia, sone, and a
I wouldn't include 3dfx though. 3dfx management sure made some bad moves in retrospect (like their buying stb & cutting off oems) but I really don't think their management was bad enough to have really done in their company. It was really nvidia that killed 3dfx in my opinion. I just read the article about the demise of 3dfx in another thread and it really sounded like their engineering talent just wasn't adquate compared to nvidia. They could never match nvidia's super fast procuction cycles and even their planned chipsets for 2 generations out from the Voodoo5 had separate geometry and texture chips. They could never have hoped to be price competitive with separate geometry and teturing chips. If 3dfx only had s3, ati & matrox (who were the majors back then) to compete with, they'd still be around today.
And how about Woolworth? It used to dominate retail but went bust only to eventually be replaced by Walmart which is a huge company that fills essentially the same niche that Woolworth did.