Mister Tristan (the 6 year old human being, not the blog), learned a valuable Ultrarunning-related skill this weekend.
When we were out in the hot tub, his nose was running, and no tissues available, I taught him how to blow a snot rocket.
That's where you hold one nostril shut while you blow vigorously, launching a blob of snot--the snot rocket. Then you do the other nostril. Naturally, there is an important component of directionality that must be well considered.
It's gross but effective, and extremely useful when the traditional nose blow with tissues is not an option.
As when you're running in the backcountry.