Well, it was rather laggy, but moving in Bembecia I seem to have inadvertently broken through the ground and fallen into the void...
Before I attempted to teleport, my Z coordinate was at -1600 and climbing (er, falling) at a fantastic rate. I will never take the ground for granted again...
Just checked and the teleport failed. Am currently at -5000 Z in a different sim now...
Oh my god my X and Y are over 1000!
Image available as proof on request. Am going to log now