Salon has a great article about how the big corporations come up with company names. Names like: Agilent and 98point6.
A few good quotes:
"We charge $65,000 per name, nut we work with you for a month. And for that month, we are basically yours."
"No one names a car Mustang or Thunderbird or Monte Carlo anymore. Instead, you have Acura. Alero. Xterra. Integra. All thoroughly researched committee decisions. All emotionally empty ... By the time they've been laundered, and pressed and packaged there's nothing left."
I've personally been through a few corporate rebrandings as an employee at some big companies. In one case, the "consultants" presented the new name to the whole company. I raised my hand and asked if the domain was available. It wasn't. Oops! That cost a pretty penny.
My favorite unused corporate name: Avantla. Contact me if you want to buy: Avantla.com
Happy Domain Hunting!