Thank you RichardP and WikiMinion
A big thank you to RichardP (sorry, no link - no browser with cut and paste available right now as I'm sitting on the floor in my lounge and using a Linux box with no GUI), who has recently added the Topic Exchange's wiki to the list of sites that his WikiMinion anti-spam bot cleans.
This is incredibly helpful for me, because I wasn't monitoring the Topic Exchange wiki well enough, and many pages have been lost after a spammer replaced them with a bunch of links and their old versions expired. This shouldn't happen any more. Once again, thank you RichardP!