I've had an account on Project Euler for a while, but I never really used it. A few years ago, I decided to start solving problems in PHP and Java. The hands-down coolest thing I learned so far was the sieve of Eratosthenes.
Anyways, I decided that it'd be cool if I posted my answers. The intention is to show others my implementation of each problem, namely because the forums on PE are closed for all of the problems I've solved thus far. I would prefer that you refrain from looking at my implementations until you've solved the puzzles yourself. Of course, I have no way of stopping you short of not posting them at all. Most of my previous answers are missing in action, but I recently decided to start solving problems using Python.
Here is the link to my Python answers repo . It works by utilizing the Pocket Euler project. This project store all of the problems in MarkDown format and provides an MD5 hash of the correct answer, giving me something to check against in a automatic way while not giving away the answers. My project provides an answer checker that is able to run my problem's solution, turn the solution into a hash, and check that hash against Pocket Euler's answer.