Map keys on keyboard to something different

$ xmodmap -e "keycode 94 = Shift_R"
$ xmodmap -e "keycode 62 = less"

Customize Ubuntu keyboard (create “pipe” key)

http://www.linguist.is/component/content/article/3-blogg/24-customize-ubuntu-keyboard-create-qpipeq-key

xmodmap:

https://wiki.archlinux.org/index.php/xmodmap