There is a 'thing' called Tax Twitter. It is, of course, virtual. It has no rules. And no formal membership. But it does exist. Those who tweet tax, from all sides, pretty much fall into membership.
Rasmus Christensen, a colleague of mine from Copenhagen Business School, is a key member. And yesterday he suggested that the assembled company should think about Tax Christmas Carols. This was my offering. You can find more here.