I've recently come across a couple sites those of you interested in history might enjoy.
WhatWasThere.com ties historic photos to Google maps to create a virtual time machine, allowing viewers to superimpose street scenes from the past over those from today. I particularly like the option to fade the historic photograph, which creates a ghost image over the present-day setting. Anyone may register to upload photographs and basic metadata on WhatWasThere.com. Currently most of the images are from the United States, but hopefully a wider range of sites will be represented as more people use the service.
History Pin created by non-profit We Are What We Do in partnership with Google also matches up historic photos and Google maps. Users can add stories about any of the represented places as well as uploading their own photos. The images can be searched by place, subject, and date, allowing you to really pinpoint what you're seeking. I wish this site had the fade function available on WhatWasThere.com, but other than that, I prefer History Pin. Because History Pin is partnered with Google, registration was a snap with my already existing Google ID.
Some archivists express hesitance towards their archives participating in sites like these, primarily because of the wide-open access. Anyone can post a photo and create metadata, which may or may not be accurate. Also, putting your images out there, you lose control over who may be subsequently using them and for what purpose. I think those are legitimate concerns, but in the balance between open access and intellectual control, I lean strongly toward access. I like the idea of history being recorded and interpreted by anyone. What do you think of these sites?