The NPR radio show "Says You!" asked the expert panel for a definition of octothorpe.
All us AWADERS knew!
For newcomers, here's an interesting thread
[url]http://wordsmith.org/board/showthreaded.pl?Cat=&Board=words&Number=39882 [url]
If that doesn't work, go to Search (top of the page here) and choose "all Forums" and "all posts" and you'll get more than you want to know about octothorpes ... there's a hint as to what it is in the thread header here!