Break a rear derailleur cable on the road?

What do you do when your rear derailleur cable breaks while on the road?

1) Praise yourself for having the foresight to have a spare cable and allen wrench in your bag?
2) Struggle on the best you can?
3) Jam a rock or stick into the dérailleur so you can ride the cassette's middle cog?

We were riding the Illinois I&M Canal trail when my buddy's rear dérailleur cable broke. There we were on a course gravel trail without much of anything in sight, no replacement cable, and rain threatening.

Without a replacement cable and on the last 20 miles of a 75 mile ride, we decided on the old-school choice number 3 from the above list.

We couldn't find a stick that would set the deraillieur in the correct position, but we managed to find a rock that did the job. The tape taken from a first aid kit wasn't really needed, but added as a precaution

Afterward I was able to remove the rock with the help of some pliers, but no damage and installed the new cable.