Related to this thread:
So, the computer stopped crashing after I deleted ~/.nvidia-settings-rc . This leads me to believe, that it isn't checked for correctness before it's used.
1. I use a recent kernel and the EXT4 filesystem.
2. EXT4 tends to lose data in case of sudden reboot or power failure (there was a long thread about it on LKML).
3. I swapped my old geforce 7600 for a 9600 without deleting ~/.nvidia-settings-rc , This made my computer crash unpredictably and also caused the nvidia settings app to interfere with video playback.
4. 1.,2. and 3. lead to a lot of lost files (set to 0 byte length to be specific). Mostly KDE configuration files. Thankfully, I keep all the important stuff elsewhere.
5. This can be used by a malicious local user to damage files of other users, make the computer reboot randomly, etc. It's a security problem.
6. Same thing can happen when migrating user accounts to a different system.
I think this should be fixed. The sooner, the better.