Some of these are better than others. Some don't have nice controlled vocabularies and are a bit wonky in the free version. Nearly all of them you can get through another interface for a fee if you need more precision in searching or to export your results. (oh, as an aside - you've got the database producer who puts the whole thing together, and then you have options for interfaces. For example, for Inspec, you can pay for access via STN, DIALOG, Web of Knowledge, EbscoHost, Engineering Village - used to be FirstSearch and Ovid, too, but I don't remember if they're still offering it. Librarians, when selecting these, have to pick databases and then interfaces based on functionality, cost, etc.). Some research databases we pay for don't actually have controlled vocabularies ( like Web of Science and Scopus) but have other features that are useful.
- ADS - the Astrophysics Data System - This is a great database that does a lot of cool stuff with linking to data and stuff, but it doesn't have a controlled vocabulary. It does have some full text, though. Actually a lot of full text.
Ageline -This is from AARP and it's on all sorts of topics about aging from economic and social to health issues. It's got a cool thesaurus and a new interface.
- Agricola - Talk about a mess of an interface. Even the folks at NAL pay a vendor to provide an interface. Funding for this has been up and down, too. It covers all areas related to agriculture. It has a controlled vocabulary.
- Citeseer & CSB- (I suppose you could put these in here, if you really want to)
- ERIC - This is done by the the Department of Education. Funding's been a little uneven (or a lot uneven)
- National Criminal Justice Reference Service - From DOJ Office of Justice Program.
- INIS - This is from the IAEA and it's got all aspects of science and related to the peaceful use of nuclear technology. Nice controlled vocabulary. Goes back to the 70s. Pretty cool. Make that very cool.
- PubMed - Everyone knows about this. Don't forget it also includes veterinary stuff, too.
- TRIS - From the National Transportation Library and the TRB (part of the National Academies). Covers all sorts of stuff related to transportation.
Oh, and there are technical report digital libraries from the government that have full text and also have controlled vocabularies. And places to get data and maps and stuff. We'll leave those for future posts.
I'm sure there are probably some other non-profits or governmental organizations with freely available research databases. If I've forgotten any big ones, please let me know. Don't forget, too, that lots of research databases are free to you from your local public library, your workplace, or your school.
update: 2/8/2010 Ageline was purchased from AARP by Ebsco. Ebsco has now closed access - put it behind a pay wall.