The Transport Museum as well, the Regatta, water sports. Talks on many subjects. Film and photos. Do your own thing - eg family tree research. Also, volunteers always needed by various organisations, covering heaps of different interests.
If nothing appeals, there's always the chance of starting up something oneself. That can range from individual projects through to group involvements.
Maybe Dover doesn't cover some interests. But from my point of view, Dover is heaven, for things to do.
