Proper password policies
A discussion of various password policies that are often enforced, their relative effectiveness and, in some cases, their harmfulness.
Email address obfuscation
A description of email obfuscation techniques in use today, and an evidence-based comparison of which ones work.
Fixed points of hash functions
Under what circumstances can (or must) a fixed point of a cryptographic hash function exist: where a string hashes to itself?
Unsung benefits of IPv6
Discussion of the advantages of IPv6, other than increased address space, such as mandatory encryption and extensibility.
Effective CPU denial of service attack using hash functions
A discussion of the exploit where, using hash collisions, a server can be DoSed using minimal bandwidth and resources.
A demonstration of a mathematical quine: a formula which prints itself when graphed.
Salt, pepper and rainbows: storing passwords properly
The proper methodology for storing passwords in a database. Covers hashing, rainbow tables, salting and peppering.
The Monty Hall Problem
The somwhat counter-intuitive Monty Hall Problem, and a quick mathematical explanation and generalisation.
The best strategy to use when choosing words in Hangman, depending on the number of guesses allowed and the length of the word.