Descriptive Problem Summary:
Byond ticks just all up and stopped, no map updates, no sleep proc processing (even new ones)

We had this before on the server but i never was around to see, i was testing a code change to make our controller use tick_usage to avoid overrunning a tick. and it triggered.

Symptoms:

No stat panel updates
No map updates
DD -> Players -> Send Announcement doesn't work.
Usr << "Msg" does work
Browse() does work (how I was able to figure out that the ticker wasn't ticking at all, and this wasn't just a map update thing)
Verbs seem to work.
Slept procs don't wake up.
Onclick event for items in the stat panel seem to work.
The moment a client disconnects and reconnects (or maybe just connects) it solves itself.