I was pursuing questions today, and ran across jQuery hotkeys plugin.
The accepted answer shows how to use
hook_form_alter() to accomplish what the OP wanted to do.
Given that a lot of work with forms involves
hook_form_alter(), should we have a "form-alter" tag?
I don't think that many people asking questions would know to use this tag, but others could add the tag as appropriate.
I am thinking that this may help people to find related questions/answers easier.