mkcd - mkdir & cd directly into it

phaidros@42:~/ #$ echo 'mkcd() { mkdir -p "$@" && cd $_; }' >> ~/.bashrc
phaidros@42:~/ #$ . ~/.bashrc
phaidros@42:~/ #$ mkcd /path/to/a/new/folder/
phaidros@42:/path/to/a/new/folder/#$ echo "Well done :) !"

Little, easy, damn useful.
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