Fired over private myspace comments.
http://www.cnn.com/video/#/video/tech/2009/05/04/am.cho.myspace.cnn
This is why I don't share my personal websites, emails, or facebook/myspace account professionally in resumes. Nor would I share any of it with future coworkers.
I signed up for careerbuilder.com and some other online job searching websites and they all asked for my 'social internet sharing' accounts or websites. The key is to just keep your mouth shut at work and not talk about it publically if all you have to say is negative. Odds are it'll get back to you in some form or another and it probably won't put you in a pleasant light. =/
I used to surf my websites from work, but I bought a clearwire internet connection and used my own laptop to do it. There was NO WAY I was going to do that on my computer, especially as a manager. After I left my assistant did it, I told her not to - that big brother could watch everything she was doing - but she did it anyway. After she was let go (for that and other reasons) they had to clean up all the crap she had put on the computer. Looked really really bad for her. =/
If I want to come on this site and complain about my boss - if my boss finds it later they should just suck it up - they shouldn't be able to fire me over it.