Sorted

written by, and read by, © Peter Howard, first published on the World Wide Web in Snakeskin

I was trying to think of the single most pointless thing I own:
the thing I have absolutely no conceivable use for.

And I decided that, narrowly beating the liquid lunch entitled
"Shakespeare's Sonnets: the Problems Solved" (by A.L. Rowse)
it would have to be
the inverse hyperbolic cosine function on my electronic calculator.