The theme this weekend (and perhaps for the next 20 days) is Santa. And while we’re used to a Santa who sits in a big chair at the mall all December while kindly pretending to give a hoot about our Christmas wishes, the Santas we’ll be seeing this weekend are, well, a more lively sort. Santacon, the annual Santa bar crawl, takes place in Portland on Saturday. And Surfriders is rounding up Santas on surfboards down in Kennebunkport. In Freeport, runners can dress up in holiday garb for a Santa-themed sprint through town. And you’re welcome to dress up as the big mad in red for any other weekend activities, like First Friday Art Walk, The Santaland Diaries, and any of the classic holiday festivals happening in towns around Southern Maine.