from the DBA Sciences page: "Database Advisor (DBA) was created to aid database users in selecting the best database for their query. DBA spawns a search process for each database vendor, and returns the hits on the query to the user. It sorts these results so the user can see where each database stands relative to the others." DBA is GPL'd, and its components are all free according to one license or another. You can even take it for a test drive...
Database Advisor from UCSD
By dchud - Posted on June 5th, 2000