I just got a new laptop and had to google again on how to set caps lock key to escape (I’m a Vim user).
sudo apt-get install dconf-tools
dconf write /org/gnome/desktop/input-sources/xkb-options "['caps:escape']"
To know your options, use the following command:
man xkeyboard-config
(MAN pages are your friend; man is short for manual)
You can also now use the Dconf GUI editor if you must (SHAME! ;) )
Type Dconf in Unity or Gnome app opener and go to the following location:
`org` →- `gnome` → `desktop` → `input-sources` → `xkb-options`
Add ['caps:escape'] to Custom Value textbox.
Cheers.