I noticed that when turning on the File Structure window, opening a source
file and enabling both the 'Track caret in editor' as 'Auto scroll to source'
buttons from the File Structure window, VS2003 (don't know about 2005) gets
stuck in an infinate loop. You have to kill VS and restart it.
I've added this to the tracker (#22238) but still thought I'd post it here
so others don't lose any work due to this.