Boris Johnson says he wants to put the fun into the London Olympics and by way of solid proof has unveiled plans for the ArcelorMittal Orbit, a 120m helter-skelter tower that will sit alongside the 2012 stadium.
Designed by Anish Kapoor, who calls his baby a "folly", it passes the fun test with top marks, partly because it gives us a chance to revive an old joke.
"It'll be good when it's finished" becomes: "It'll look fine when they take the scaffolding off."
But what about the clunky sponsor-heavy name?
ArcelorMittal is a big steel company, which doesn't sound much like fun, unless you count spot welding among your hobbies.
Luckily, it's easy enough to drop the first part and just call the thing the Orbit, a bit like we all call it the London Eye, not the Merlin Entertainments London Eye. Sneakier business types give us no such chance. It's simply the O2, or The Emirates.
The sponsor's mark can be a good thing, mind. If you went into a shop, even at this time of year, and asked for an egg, they'd give you something delivered by a chicken, rather than an Easter egg, which is what we all want. Yes, that was hint.