Random number generation and RFC 1750
- Information regarding best practice random number generation for cryptography.
- http://tools.ietf.org/html/rfc1750

Claude Shannon's Communication Theory of Secrecy Systems
- 1949 Bell Labs research paper on theoretical secrecy and perfect encryption cryptography.
- http://www.research.att.com/~njas/doc/shannon.html

Cryptodox
- A community wiki. Basic cryptography theory and information security resources.
- http://www.cryptodox.com/

Introduction to Cryptography
- Elementary information on cryptographic theory, digital signatures, protocols, and cryptanalysis.
- http://www.ssh.com/support/cryptography/introduction/

Bibliography on Secret Sharing Schemes
- List maintained by Douglas Stinson and Ruizhong Wei.
- http://www.cacr.math.uwaterloo.ca/~dstinson/ssbib.html

Boolean Function Nonlinearity
- A detailed discussion of cryptographic nonlinearity, what it means and how it is computed, with active JavaScript panels to perform the computation.
- http://www.ciphersbyritter.com/JAVASCRP/NONLMEAS.HTM

Index of Cryptography Papers Available Online
- A research tool for the cryptography community maintained by Counterpane Systems. Over 400 papers online.
- http://www.counterpane.com/biblio/

Chaffing and Winnowing
- An interesting paper by Ron Rivest about providing confidentiality without encryption.
- http://theory.lcs.mit.edu/~rivest/chaffing.txt

Paul Garrett: Crypto and Number Theory
- Lecture notes for a course on cryptography and number theory.
- http://www.math.umn.edu/~garrett/crypto/

Foundations of Cryptography
- Oded Goldreich. A public domain book available on-line. Only partially completed.
- http://theory.lcs.mit.edu/~oded/frag.html