Free literature databases: a selection

  Here is a selection of databases or search engines that are free on the Web, listed by broad category.

Biomedicine/Evidence-Based Medicine:
PubMed [U.S. National Library of Medicine]
NLM Gateway [U.S. National Library of Medicine]
The Cochrane Collaboration [citations only, without subscription]
Cochrane Reviews abstracts & summaries
Centre for Reviews and Dissemination Databases
  [including Database of Abstracts of Reviews of Effects (DARE)]
TRIP Database: Turning Research into Practice 
Scirus for scientific information only

Education/Medical Education:
ERIC [Education Resources Information Center, U.S. Dept. of Education]
TIMELit: Topics in Medical Education  [Centre for Medical Education, Dundee]
RDRB: Research & Development Resource Base (in CME) [University of Toronto]

Complementary & Alternative Medicine:
PEDro (Physiotherapy Evidence Database) [Centre for Evidence-Based Physiotherapy (CEBP)]
OSTMED (The Osteopathic Literature Database) [to 2003]
Index to Chiropractic Literature [CLIBCON]

General:
Google Scholar [Advanced Scholar Search]
Google Book Search [Advanced Book Search]                             *