Since reading that xkcd, I use phrases as passwords, using a simple Ruby script to generate them:

  w = File.readlines('/usr/share/dict/words').map { |w| w.chomp }.reject { |w| w !~ /^[A-Za-z]+$/ }; 3.times { print w[rand * w.size] }; puts

I generally get an easy to remember password after about 3 tries. The biggest issue I have with this is typing in passwords on mobile devices.