This article on volunteers helping with the hunt for Jim Gray is interesting to read. I hope it helps find him; and maybe that the ad hoc efforts lead to something more permanent that could help others in similar situations.
Update (from Tim). Charlie Catlett wrote on Dave Farber’s IP list:
“The Amazon Mechanical Turk team has created a site where there are
40,000 images from the past 2-3 days that volunteers can search and flag
images. At mid-day today we are expecting another batch of images from
the Canadian space agency, which retasked a satellite to fly over during
the past 24 hours.”