I've been really focusing on productivity and developer skills, these are quotes from UNIX manuals, Pragmatic Progammer and more... I hope to keep building upon the list!
I pipe a random line from here through cowsay in my .bash_profile/.bashrc (homebrew requires 'gsort' for the -R flag)
gsort -R quotes.txt | head -n 1 | cowsay -f satanic.cow