The 20th annual Richmond Folk Festival is coming up Friday through Sunday, September 27th through the 29th. And this week (Sunday September 15, 1:00-3:00 PM on WRIR, for two weeks afterwards at wrir.org/listen, check your local listings for airing on other radio stations, and any old time at my podcast site) it’s time for Global A Go-Go’s annual preview of the Folk Festival.