Well,I suppose any building that isn't actually a square box could be somewhere on the ladder of public art, most often quite near the bottom rung but occasionally sublime. A lot of public art, due to its grand scale, might not be too subtle in its intimate details but can be very striking, even inspiring. I take it you're thinking more of individual pieces rather than squares in cities, bridges or collections of buildings. There's the statue of Wenceslas on horseback in Prague's Wenceslas Square, hard by the spot where Jan Palach set fire to himself. I like that one, but then I'm a known vulgarian. On the new road junction just outside Barnstaple in Devon, on the big roundabout, there's a henge- like collection of massive standing slabs, supposedly a mock-up of a prehistoric monument. The locals don't like it because the stones are Cornish slate! That's just risible, but at least it gets people talking. There's the willow man ("the Angel of the South"), tearing his way towards the Westcountry, next to the M5 near Bridgwater. We love him, though the birds keep nicking bits of him for their nests. And bring on the Milton Keynes concrete cows!