The imaginary friends thread in GQ got me reminiscing, both about my imaginary friend from years back and about a system we used to have for managing a problem that has plagued humanity for so many years: that of not having enough people for a proper game of baseball.
If we had a ludicrously low number of players, we might have the entire team on base at the same time. When we got back to the beginning of the rotation, who would bat? George Will probably would not approve of the way in which we solved the problem: we would assign an “invisible man” to the base the person now batting had previously occupied. I don’t remember how or even if an invisible man could be tagged out. Could a person say “Eh, I think I just saw my invisible man steal home,” and not get thrown out of the game by the invisible umpire? Maybe we were too honorable for that kind of trickery. Or perhaps not clever enough?
How about you guys? Any variations on this idea?
Yes, we played this. An invisible man could only proceed to the next base when forced to by someone taking his old base. As far as tagging out: suppose you have an invisible man on second and a regular runner on first. When the batter hits the ball, you can tag third any time before the runner at first reaches second.
And Earl, you are a far, far better person than I am for not having these detailed childhood rules still taking up space in your brain. 
There were a few ways to play with an invisible man.
Usually, we had enough people so that the invisible man would be behind another runner. There might be a real runner on 2nd and an invisible man on 1st. Then the invisible man would stay a base behind the real runner, and you could force him out (e.g at 2nd) before the real runner got to the next base (e.g. 3rd).
If we didn’t have enough people to do that, we would usually tie the invisible man to the batter. The invisible man moves as far as the batter does. If there’s an invisible man on 2nd and you get a single, he moves to third. No one moved on an out. It was pitcher’s hand, so you usually didn’t have to worry about tagging bases that no one was running to. The lead runner who was forced to move got out when the pitcher got the ball. For instance, if there were ghost runners on first and third and the batter hit a ground ball that the pitcher got before he reached 1st, then there would still be runners on 1st & 3rd, with 1 more out (guy on third stays at third, guy on 1st forced out at 2nd, batter reaches 1st).
The other way to do it was to only have ghost runners move if they’re forced to. So if you get a triple, then a double, then a single, then no one has scored and the bases are loaded. This is only fair if all baserunners are ghost runners - otherwise it gives a huge advantage to real runners.