SciRide Finder is a newly launched search tool that searches Medline/PubMed, but it limits the search to just those “statements, numbers and protocols” which cite other publications. A fine idea, but the core concept may initially be a little difficult for humanities scholars to fathom. You can see what they’re talking about, in this visual example…

SciRide Finder appears to have crashed under the initial surge of traffic, but is “under maintenance” and should be up again soon.