BeeCrypt is an open source cryptography library that contains highly
optimized C and assembler implementations of many well-known algorithms
including Blowfish, MD5, SHA-1, Diffie-Hellman, and ElGamal. Unlike
some other crypto libraries, BeeCrypt is not designed to solve one
specific problem, like file encryption, but to be a general purpose
toolkit which can be used in a variety of applications.

The BeeCrypt library currently includes: 
   - Entropy sources for initializing pseudo-random generators 
   - Pseudo-random generators: FIPS-186, Mersenne Twister 
   - Block ciphers: Blowfish 
   - Hash functions: MD5, SHA-1, SHA-256 
   - Keyed hash functions: MD5/HMAC, SHA-1/HMAC, SHA-256/HMAC 
   - Multi-precision integer library, with assembler-optimized routines 
   - Probabilistic primality testing, with optimized small prime trial
     division 
   - Discrete logarithm parameter generation over a prime field 
   - Diffie-Hellman key agreement 
   - DHAES encryption scheme 
   - ElGamal signature scheme (two variants) 
   - Basic RSA primitives and key pair generation 

WWW: http://sourceforge.net/projects/beecrypt