Return of the Donnybrook!

A good number of comments on this site, I've noticed, begin "Off topic, but..." The zeal of commenters for discussing a given subject is undeterred by mere irrelevance: A post about Say's Law invariably winds up hosting a thread about pistachio nuts (or, more usually, abortion). At the same time, the churn of new posts sometimes interrupts a perfectly good argument, or slices up into several different threads a discussion that should really embrace them all. For these reasons, I've resurrected an old feature on this site, the Donnybrook: free-standing comment threads that are not tied to a particular post, but have a life of their own. (After all, it's your site: I just work here.) I've set up three of these to start you off. You'll see them posted at the top of the right-hand column. The first, provocatively named "Off topic, but..." is an open thread, for posting items that have nothing to do with anything previously posted, but might be of interest. The second and third are self-explanatory, broad topics of continuing interest. I'll leave them up for as long as they seem current. (Feel free to suggest some more.) Have fun.