Classical Logic
   Introduction to classical logic, including completeness and Löwenheim-Skolem theorems; by Stewart Shapiro.
   http://plato.stanford.edu/entries/logic-classical/

Computability Logic Homepage
   Main online source on computability logic - a recently emerged formal theory of computational tasks and resources. Maintained by G.Japaridze.
   http://www.cis.upenn.edu/~giorgi/cl.html

Introduction to Mathematical Logic
   Hyper-textbook for students by V. Detlovs and K. Podnieks.
   http://www.ltn.lv/~podnieks/mlog/ml.htm

Mathematical Logic and Foundations
   From The Mathematical Atlas, a resource of mathematics maintained by David Rusin. Extensive resources related to logic and set theory.
   http://www.math.niu.edu/~rusin/known-math/index/03-XX.html

Mathematical Logic around the World
   A rich collection of links to logic-related websites.
   http://www.uni-bonn.de/logic/world.html

Mind Versus Goedel by Damjan Bojadziev
   Compares the mind to advanced computers and artificial intelligence, as Goedel would possibly view them.
   http://nl.ijs.si/~damjan/g-m-c.html