最新版をwgetで持ってきてunzip
$ wget -N http://chromedriver.storage.googleapis.com/2.15/chromedriver_linux64.zip -P /tmp
$ unzip /tmp/chromedriver_linux64.zip -d /tmp
/usr/local/share において/usr/local/bin にシンボリック
$ sudo mv /tmp/chromedriver /usr/local/share
$ sudo ln -s /usr/local/share/chromedriver /usr/local/bin/chromedriver
確認
$ which chromedriver
いいね!