I spent 7 years with the same (American) company after bombing out of college at 17. I worked for them first in Wembley, then up to Aberdeen for a few years, that back down to London, where I worked in their flagship sales office in Mayfair.
I spent time as a desktop support guy (which is probably just about as stressful and technical as a technician job in a school), then an email administrator (back in the days when my modem used to phone the States 4 times a day to transfer all the email back and forth), then running the internal support department (easiest job of my life), and finally as a Mr Fix-it in Mayfair.
One big thing about the corporate world is the perks. You'll be lucky to get huge bonuses, share options, non-contributary pensions or private health care working for a school (not that these are assumed in a 'real world' job). On the flip side, I wouldn't even get Christmas Day off unless I took it out of my holiday allowance...
To be honest I think I got lucky with the various roles and bosses I had, in that I was never particularly under too much pressure, but I basically ended up bored. Yeah, the expense account, the corporate Amex card, the being taken out for dinner/drinks by clients, the trips around the UK/Europe, etc. were great, but I basically wasn't doing anything for a living. And then there's the back-stabbing, in-fighting, and corporate ladder-climbers that just drove me bonkers...
Add all this to a commute on the world's oldest underground mass-transit system and it was pretty easy to turn my back on it all.
The education thing was an accident, but this is the second school I've worked at now, and it's far easier, not so badly paid (once I take off the thousands that travel used to cost) and I get the time back that a commute used to rob me of. It's still only a means to pay the bills, but I'd rather be here than the corporate world, any day.