I went to a security presentation yesterday with one of the guys from work which summarised some of the cooler Blackhat and Defcon presentations from Las Vegas this year.
One of these presentations demonstrated the use of the open API’s available for some of the social media sites. The below list represents some of the search engine I’ve found that allow search words to be queried against publicly available information. I’ve found that these searches far exceed what is indexed on the social media site search option.
Google Buzz API Browser: explore what’s publicly visible through the Google Buzz API
Facebook API Browser: explore what’s publicly visible through the Facebook Graph API
Wink People Search
Showdan HQ – Computer search engine (looks for MAC address)