If you’re an Org user, you probably know that you can assign a priority to TODO items. By default, the priorities are A, B, and C but with a bit of trickery you can extend the ranges to 0–9 and A–Z.
I never use priorities but Raymond Zeitler does and after figuring out the above trickery he thought it would be useful to have an ultimate priority a sort of “drop everything and do this immediately” priority. He decided to make this priority 100 times the highest priority and to designate it with !.
The solution wasn’t straightforward but it wasn’t too difficult either. The thing about Emacs is that it’s easy to check the source code to see how things are done. It turns out that Org has a org-priority-get-priority-function variable that contains a function that Org calls to get the priority from the priority cookie. Zeitler wrote his own version to check for a ! and return the high priority if it’s found. If not, then it calls a slightly modified version of the normal function.
As I say, I don’t make use of the priority mechanism and have no idea how many people do but if you’re one of them and are looking for a way to specify an extraordinary priority, take a look at Zeitler’s post. You can cut and paste his code if you’re interested.