I'm not sure if it's really a crash but it sure does look like it.
This never happened on my 9.04 Ubuntu before. I chose to install Xubuntu 12.04 since it's much lighter and I expected it to work better on my EeePC 701.
The problem is that this happens whenever I try unmounting external drives. It doesn't exactly happen all the time but it happens every once in a while. Quite annoying, really.
I've taken pictures of what happens...
How do I fix this? Or, at least, what causes this so I can avoid it?