3 projects I’d like to see happen
An online collaborative genealogy tree that would connect all the persons who live or have lived. With photos, biography, maps… The best trial is probably werelate.org.
A Google Earth based collaborative historical atlas with links to sources, illustrations and videos. Should include various maps like frontiers, demography, battles… Something like that :
A platform for online collaborative science that would allow everyone to propose a project or to join one. Should include wiki, Tex, peer-review system, bug report, photo gallery, etc. I already discussed this here. Colabscience.com could be a good starting point.