A few years ago on a tour to the Grand Canyon with my friend Steve, he was on a new (to him) bike and the fuel gage wasn't working. He ran out of fuel twice, requiring my daughter and I to go ahead, fill up a small gas can, and return so he could make it into the next town.
We called it the gas can of shame.
He had to bungie it onto the back of his bike, kind of like wearing the scarlet letter letting everyone know he had run out of fuel—not once, but twice. In the rain.
A few years later on a different tour, I had underestimated the distance from the last fuel stop before the Canadian border to the first available fuel stop in Montana (riding in a stiff head wind) and ran out of fuel myself. Although one of my friends had a hose, it wasn't quite long enough to reach from one bike to another and required a little encouragement to get the siphon going—followed by a mouthful of premium unleaded.
I have yet to live that down and am reminded of it every time we're together (since Jim, another one of my friends, had volunteered to get the siphon started and got the mouthful).
After that, I purchased this plumber's siphon and have given it a place in the bottom of my saddle bag in hopes that because it's there I will never again need to use it.