Stuck on a puzzle that requires you to become a codebreaker? The Secret Code Breaker can help. The site provides a number of free codebreaking tools that I’ve found far more useful in some circumstances than many other online tools.

One of the most useful ones is the Monoalphabetic Substitution Cipher Solver – while there are many cryptogram solvers available on the web already, this one has the ability to solve cryptograms when the spaces are removed.

There is a wonderful library of tools useful in cracking classical ciphers available at rumkin.com. This is typically the first place I go when trying to solve a puzzle that involves cracking a cipher.

If you enjoy wordplay (and, frankly, who doesn’t?), then you’ll love the National Puzzlers League. The NPL is a self-described eclectic crowd who enjoy all forms of wordplay and are continuing the traditions of “The World’s Oldest Puzzlers’ Organization”.