Anyone with a pair of eyes (sorry blind people) can participate. They’re called the Citizen Science Projects, they’re run by Zooniverse and they are looking for volunteers. They’ve got a new project called Old Weather where they are trying to collect weather records from WWI naval logs in order to improve their computer models so they can make better predictions about changes in our climate. Pick a Royal Naval vessel, go through the logs, record the weather. You also record personal and political events and learn about the boats. Great for naval and weather nerds, but it really helps if you can read peoples’ handwriting.
There is also the Moon Zoo, where you are shown photographs of the moon’s surface and mark what you see. You can do a crater survey where you identify craters or boulder wars where you note areas with boulders. Galaxy Zoo in which volunteers are asked to look at pictures taken by the Hubble Space Telescope and identify different types of galaxies by their shape. If you like your nerding a bit racier, there’s Solar Stormwatch. All the excitement of stormchasing in the sun without the dangers of being burnt to a crisp.
Zooniverse have tutorials on how to participate in each of their projects, and they get quite addictive.
80 million people play FarmVille – this at least isn’t a total waste of time!