"Alan OBrien" wrote in message
o.uk...
There is a sign on the northbound platform at the Oval which I think is
unique:
http://photos1.blogger.com/hello/46/...0/Image010.jpg
I have mentioned this before and the most sensible answer I got was that
it
stands for All your base are belong to us!!

Looks like a sign to denote some infrastructure (track / signalling / etc.)
feature to me. Although, does it stand for Temporary Speed Bump?