The first one from hacker news, aptly titled "How I Hacked Hacker News (with arc security advisory)"
and the 2nd, a welcome-back-to-the-blogosphere-tptacek post on the matasano blog: [Typing The Letters A-E-S Into Your Code? You're Doing It Wrong!]
PS. for those going, man i wish someone would break down the important crypto stuff for me in a way thats understandable without being patronizing, there is Chris Eng and his owasp talk on [Cryptography For Penetration Testers]