This requires rooting, which (unfortunately) comes with all sorts of strings attached and ugly rough edges. I'd rather have the idea of a flexible permissions model built into the OS.
Pry-fi (randomise MAC address when probing for wireless networks), Titanium Backup (backup that doesn't suck), most advanced network tools, changing FDE password to be different to lock screen password, running an sshd, detecting IMSI catchers, most performance fixes/optimisations, even just basic full filesystem access - all need root too.