I was going to suggest Westnoth - it is one of the absolute jewels of Linux gaming. Another one I like is "Pioneers" which is a neat little implementation of the "Settlers of Catan" boardgame. Which has it's own free online client tha is more active online but a bit buggy & laggy. Pioneers is good for a 15-30 minute game against 3 computer players. Use the official client to play against other human beings :)

Bigpond & Optus are not involved in the trial

Keith played to a click track. I remember reading an interview with him when he described what it was like playing stuff like "Baba O'Reilly" & "Won't get fooled again" live when the synth parts were sequenced. Can't remember WHAT he said (it was a long time ago!!) but The Who were definitely using click tracks live in the '70s.