Actually yes. Usually it happens on one morning when I turn off the screen lock and I notice that it takes too long time to change workspaces. CPU usage is practically 0 and the system has just started to swap, so it's not that hard to kill firefox and opera. I don't like to lose the shell histories, the 100+ opened files in vim, etc. so I try to avoid logging out, even though I have to do it every other month when the desktop environment leaked too much memory.