Every programmer should read the source to abort() at some point in their life.
Plan 9's abort causes an access fault, causing the current process to enter the `Broken' state.  The process can then be inspected by a debugger. Pretty elegant.<p><a href="http://plan9.bell-labs.com/sources/plan9/sys/src/libc/9sys/abort.c" rel="nofollow">http://plan9.bell-labs.com/sources/plan9/sys/src/libc/9sys/a...</a>