Beveled caulk-tip tip
Before caulking in a corner, I cut the end of the nozzle at a 45° angle, then draw a solid line with a felt-tip pen on top of the 45°cut along the length of the nozzle. I also draw a dotted line on the bottom of the 45° cut. In this way, I always know where the 45° angle is even when the nozzle gums up.
Alex Oppedijk, Forest Knolls, CA