Very strange Service Broker and TempDB problem

In a nut shell was that the tempdb was taking all the drive space which was allocated to it. On this system, tempdb is sitting on it’s own 50 Gig drive, so SQL can take the entire thing if it needs to. The problem was that sp_spaceused was showing that the entire database was empty, but we were getting out of space errors when running queries which needed to use tempdb.