Firefox, like the other major browsers, can be a real memory hog. Often when I have a lot of tabs open and I've been browsing for a while, Firefox will start locking up. The easiest way to fix a lock-up seems to be to kill the process and restart firefox. Nowadays most of the other major browsers seem to be able to handle a large number of tabs and memory usage without totally locking.
I know this must be a common problem, because I've seen it happen on another computer (probably more) which doesn't have the same exact settings as one of my computers. It usually happens once firefox has used up all the available memory and starts swapping.
Is there a way to configure or alter firefox so that it doesn't lock up when there are a large number of tabs open?