Rockbox on SanDisk Sansa Clip / Clip+

wget http://download.rockbox.org/rbutil/linux/RockboxUtility-v1.4.0-64bit.tar.bz2 -P /tmp
tar xjf /tmp/RockboxUtility-v1.4.0-64bit.tar.bz2 -C /tmp/
/tmp/RockboxUtility-v1.4.0-64bit/RockboxUtility
wget http://mp3support.sandisk.com/firmware/clipplus/clipplus01.02.18.zip -P /tmp/

Links
http://www.rockbox.org