Pick-n-mix by sending something like this as user data to your EC2 instance at startup:
#include
https://raw.github.com/iconara/ec2rc/master/setup.sh
https://raw.github.com/iconara/ec2rc/master/install_basic_packages.sh
https://raw.github.com/iconara/ec2rc/master/install_rvm.sh
https://raw.github.com/iconara/ec2rc/master/install_rubies.sh
https://raw.github.com/iconara/ec2rc/master/configure_tmux.sh
https://raw.github.com/iconara/ec2rc/master/configure_sshd.sh
and mix-n-match with your own stuff too.