Put public keys for a github user in ~/.ssh/authorized keys with mucho ease

get-keys-for-github-user.sh

IFS="$(printf '\n\t')"

mkdir -p ~/.ssh

if ! [[ -f ~/.ssh/authorized_keys ]]; then
  echo "Creating new ~/.ssh/authorized_keys"
  touch ~/.ssh/authorized_keys
fi

user=$1
keys=`curl https://api.github.com/users/$user/keys | grep -o -E "ssh-\w+\s+[^\"]+"`

for key in $keys; do
  echo $key
  grep -q "$key" ~/.ssh/authorized_keys || echo "$key" >> ~/.ssh/authorized_keys
done

Use this like so:

$ curl -L http://bit.ly/gh-keys | bash -s <github username>

http://bit.ly/gh-keys redirects to the raw version of this script; curl's -L tells it to follow redirects, and bash's -s tells it to use STDIN as the script and the arguments as the positional parameters

At the time of writing, https://github.com/musically-ut.keys will output the keys in authorized_keys friendly format and in plain text. That will avoid having to grep through the JSON looking for the keys.