The Old Weather project

I'd not thought of this, but it's a wonderful use of people's time and interest. The Old Weather project has people looking at Royal Navy ship's log books from around the time of World War I to recover worldwide weather observations. The project then uses the transcriptions for climate model projections. There's an historical element, too: the website says that historians will use this information to track past ship movements and the stories of the people on board.

The Old Weather project