Dual Identity Combinators
   Article by Katalin Bimbó presented at the 20th World Congress of Philosophy. Investigates the addition of identity combinators, in the formulae-as-types sense, to combinatory logic.
   http://www.bu.edu/wcp/Papers/Logi/LogiBimb.htm

Kolmogorov Complexity in Combinatory Logic
   Online article by John Tromp. Kolmogorov complexity is a recursion theoretic characterisation of randomness.
   http://www.cwi.nl/~tromp/cl/cl.html

Lambda
   An online introduction to the lambda calculus by Lloyd Allison, complete with a web form that will evaluate lambda expressions.
   http://www.csse.monash.edu.au/~lloyd/tildeFP/Lambda/

Perl Contains the Lambda-Calculus
   Explains why this computer program is well suited to apply to functional application.
   http://perl.plover.com/lambda/