Research

• Dynamic epistemic logics
• Logic programming
• Modal logics

Resources

General

• Wikipedia
• Scholarpedia
  
• Knowledge Rush (encyclopedia and books)
• Project Gutenberg
  
• Google Scholar
  

Computer Science

• SpringerLink - computer science
• ACM Digital Library

Mathematics

• Encyclopedia of Mathematics
• MathWorld
• Planet Math Encyclopedia
  
• JSTOR mathematics journals
• SpringerLink - mathematics
  
• AMS Notices and Bulletin
• Cut the Knot
  

Logic

• Synthese
• Journal of Symbolic Logic
• Bulletin of Symbolic Logic
• Studia Logica
  
• TARK -- Theoretical Aspects of Reasoning about Knowledge
• Journal of Logic and Computation (subscription required)
  

Philosophy

• Stanford Encyclopedia of Philosophy
• Internet Encyclopedia of Philosophy
• Journal of Philosophy of Science
• The British journal for the Philosophy of Science
• Mind