A Mylar balloon I bought weeks ago for Dr. Mrs. Q’s birthday has been holding its helium astonishingly well, but has now lost enough that its density is almost exactly that of air. It doesn’t hug the ceiling or the floor, but slowly traverses the room, carried by air currents too weak for me to feel, I guess. And here’s the thing: as I sit here working, it keeps — well — visiting me. It’s kind of creepy, when it slowly floats into my peripheral vision and then taps me once or twice. Hey. Balloon here. OK, moving on. See you later.