Close the lid, it goes to sleep. Open the lid, it wakes up. Windows and Linux have yet to master this simple task.
Update: Dear downvoter, please have a look at this evidence: http://dl.dropbox.com/u/144454/lid.png
Seriously, I never had this kind of problem with Linux. I am having them now, but I have nobody to blame but myself for running a beta OS (Ubuntu 11.10)
Harumph!
(But I still like Ubuntu, overall.)
I actually don't care what DE or window manager I use, my computer is just a place to hold a browser, a terminal window, and some development tools. All I require is that it stay out of my way and not make me notice it.