[JonnieCache]

    All art is quite useless
        - Oscar Wilde

Perhaps "pointless" or "aimless" might be better than useless, but a useless item can be a item which exists merely to delight the mind/spirit. Of course, internet pedants and other cutting edge point-missers would likely argue that this is in fact itself a use. Such is the way of things.

Maybe "intrinsically motivated" would be a more HN compatible term.