The boards make good signs, there's a holiday accommodation house up the road with an old surfboard painted white, with signwriting on it (fins and all!) looks good, otherwise I saw one of the 'younguns' on seabreeze made some shelving out of one, by ripping it lengthwise......
Personally, I'd get hold of a heavy-duty spring, and swivel-plate, and make a practice simulator setup in the backyard

......at the end of the day, remove rig, store it whole (not like you'll use it on the water), the kids have a surfboard simulator as some playground equipment....

Gotta go now, just gave myself the idea for my old stuff up in the garage trusses.