Favourite error messages!

What's your favourite error message, /anus/?

Mine is malloc.c:3096: sYSMALLOc: Assertion `(old_top == (((mbinptr) (((char *) &((av)->bins[((1) - 1) * 2])) - __builtin_offsetof (struct malloc_chunk, fd)))) && old_size == 0) || ((unsigned long) (old_size) >= (unsigned long)((((__builtin_offsetof (struct malloc_chunk, fd_nextsize))+((2 * (sizeof(size_t))) - 1)) & ~((2 * (sizeof(size_t))) - 1))) && ((old_top)->size & 0x1) && ((unsigned long)old_end & pagemask) == 0)' failed.!

I like this one from where both drives of the mirror set died (of course it happened on a Sunday and resulted in a trip to the cage to fix it):

root@admin3:~# init 6
init: Not being executed as init
root@admin3:~# reboot
-bash: /sbin/reboot: Input/output error