Updating keymaps in X11 (Linux)

AKA turning off the flippin' Caps Lock key - could also be used to make that

weird symbol at the top left of an Apple keyboard into a hard escape key amiright?

Create a file at touch ~/.Xmodmap with the following contents:

clear lock
keycode  66 = Control_L NoSymbol Control_L NoSymbol Control_L
add lock = Caps_Lock

Ubuntu should pick this up on restart but if not, add a file ~/.xinitrc

if [ -s ~/.Xmodmap ]; then
    xmodmap ~/.Xmodmap
fi