We have an upscale toy shop just a few blocks from our house. It stocks plenty in the way of erector sets, junior chemistry sets, and learn-to-read books. I used to love the place, but I don't think I'll be going back much any more. They got rid of their bins of 25-cent toys (often more like $1.95 these days, but you get the idea), which was the only draw for me. I have a small sack of party favors and cheap diversions: whee whistles, pocket Slinkys, Silly Putty, snap bracelets, one-finger squirt guns, Boinks, powerful mini-magnets, holograms. They range in price from 25 cents to two dollars, and each has provided at least an hour's entertainment per dollar spent. In memoriam to the passing of what I called the cracker-jack toy bin of Learning Express, I pause to describe three great two-bit toys you may not have seen yet.
The tippy-top. A tippy-top is a nearly spherical top with just a nub of a handle, closely resembling a cherry pepper. They tend to be heavy for their size, usually made of wood. The amazing thing about a tippy-top is that, when spun, it flips itself upside down to spin on the handle, with the large mass perched precariously on top, in defiance of all intuition that would have masses seek the lowest available point. The physics underlying this phenomenon have yet to be explained to my satisfaction.
Boinks. A boink is a sleeve of woven plastic fibers, resembling a Chinese finger trap. They can be stretched or squashed, or have their ends tucked inward to produce a neat funnel shape. What they're best at, however, is springing. Just compress the four-inch tube into a half-inch one, trying not to let your fingertips slip into the dilated ends, and hand it to a friend for inspection. When released, a boink can easily jump five or six feet. If the air currents are on your side, it can cross a small room. I have yet to see someone who wasn't surprised at how much jump so weak a spring can demonstrate.
The third of my el cheapo toys doesn't have a name, at least none that I know. I got mine as an advertising gimmick, like ballpoint pens with the company logo. It's made of hard, transparent plastic, and resembles half of a long, narrow ellipsoid, cut lengthwise. It isn't a true ellipsoid, though, as the mass is distributed at an angle to the major axes. Set curved side down and given a tap to start it spinning counter-clockwise, it slows as it spins, at the same time beginning to rock from end to end. Eventually, it stops spinning entirely, and the potential energy built up in the rocking motion translates into spinning again ? in a clockwise direction. Ask an engineer to explain it to you; it's fun to watch them try to put the mechanics into terms a non-engineer can grasp.
Get a few of your own. They're swell for fidgeting, make long lines at the bank bearable, and can start some interesting conversations, especially if you hang out with scientifically sophisticated friends.