An anonymous reader sent me this URL, which explains a constant, multiple-browser crashing problem. His analysis indicates that if you have a UFS disk and it's named "/," then you'll see this problem.
I'm not sure how many Mac users this might affect; I think the percentage using UFS is actually quite low, given that HFS+ is the native file format. But if you're having browser crashing issues, perhaps this is the cause...
Mac OS X Hints
http://hints.macworld.com/article.php?story=20040630060147565