While cleaning my hard disk I have found a zip file with a few old Mac OS X cracking tuts. Most are for PPC but they are still useful for learning reversing techniques.
Grab it here: tuts.zip (SHA1(tuts.zip)= 3a0e1729e811deb7b7e8e19e0d6a61c9e3831b84)
My free time is almost zero since GMAT study is taking every second I have (well, Afro Samurai/The Godfather 2 are taking something too).
A score higher than 700 is not an easy task.