Years ago, my mother gave me a gift of a simple battery-powered alarm clock that was designed like a Rubik's Cube. Only the top layer would twist, and it was used as a knob to set the mode of time, alarm, temperature.

I used it daily for many, many years, but it was inherently infuriating and shameful, as are all gifts from my mother. The Cube design it carried was permanently jumbled. There were stickers all over it, in standard Cube colors, representing its jumbled state, and of course, since it was a clock and not configurable, there was no way to match the colors and "solve" it.

I was forced, every day, to stare at a permanently unsolved, unsolvable Cube, after I had mastered it so many years ago, algorithmically, and I was able to solve a standard Cube in 63 seconds, but I could do nothing about this infernal clock.

Well, I wasn't forced. Sure, I could just stop using it. I could purchase another clock that wasn't shameful. But you know how mother-son relationships can be. Anyway, I finally destroyed it with great satisfaction, and the Unsolvable Cube troubles me no more.