Catherine Pepinster: From towers to gherkins

I'm not known for my fondness for football; I can just about identify David Beckham when he pops up in adverts for Marks & Sparks. The last footballer before him to register was probably George Best. But even I feel regret as Wembley's twin towers come down (and was I considerably cheered by the white turrets' refusal to budge yesterday, causing the demolition men to delay turning them to rubble till Monday). As a child I liked to spot them on the west London skyline; as a student I knew I was nearly home when the train cruised past them on the journey back from Manchester. Nostalgia is as powerful a reason for our love of buildings as it is for our fondness for old movies or, say, the syrupy Sixties songs of Burt Bacharach. That trip to Paris as a small child? You've loved the Eiffel Tower ever since. That extraordinary picture of St Paul's cathedral standing proud amid the flames of the Blitz? It makes you come over all patriotic, even if you wouldn't be seen dead at a royal walkabout.

But think about those buildings again. Just as the music that makes us sentimental is usually of the slower, romantic variety, so the landmarks that we love don't come in all shapes and sizes. They're either round or they're pointy. But square or rectangular? Forget it. No one feels any fondness for the boxes that are really useful to us: the offices and the retail warehouses, the supermarkets and multiplex cinemas. The boringly practical does not inspire delight.

Yet buildings need not be so tedious. Designers today can play with a building's form in a way that was until now impossible. The combination of computer technology, sophisticated building techniques and the genius of people such as Nicholas Grimshaw, Richard Rogers and Norman Foster mean that extraordinarily shaped buildings are being created. The latest of these is Foster's wondrous Swiss Re building in the City of London. Better known by its nickname, the Gherkin, it has become an instant landmark, a glittering, shameless flirt of a building on the capital's skyline. The blue and green lights used to decorate it have turned it into a giant Christmas bauble, with its facets shimmering against the night sky.

Gherkin is an odd nickname but it's certainly more polite than some of the things Foster's tumescent tower might have been called. Ever since Mr Otis invented the lift and made the early skyscrapers of Chicago and New York possible, architects and their patrons have been unable to resist having their phallic symbols thrust higher and higher into the sky. Now technology, as Foster proves, can help designers mimic the penis even more effectively. And the Gherkin certainly puts conventional dreary, grey office blocks in their place.

Not that we're likely to see too many buildings like the Gherkin, though; the cost of a complex structure usually puts paid to the ambition of designers. But buildings are more than just the visions of architects and their clients. They are the product of our society – its wealth, its technology, its traditions. That is why they matter so much: they tell us who we are, or are least, who we'd like others to think we are.

In the 19th century, the great town halls suggested the Victorian virtues of civic pride and civic responsibility. In the Twenties, when JW Simpson designed Wembley Stadium, complete with its Lutyens-inspired twin domes, for the British Empire Exhibition, the great buildings of the day conveyed the mood of the age. A growing love of leisure, speed and power was encapsulated by the architecture of structures for recreation, transport and work.

Today the best of our buildings seem to be nearly always for big corporations; think not only of the Gherkin, but the tower of Canary Wharf, or Richard Rogers' inside-out edifice for Lloyds. When it comes to our non-working lives – the shops, the cinemas, the homes we live in – most clients are too timid and planners too cautious to allow anything more adventurous. The places we inhabit when we're not at work are getting more and more soulless. Yet the best buildings are the opposite of this. They're like people; as they age, they acquire character, and our fondness for them grows. That's why I'm mourning the passing of Wembley's twin towers. But I'm thrilled by the arrival of Foster's Gherkin: the brightest new kid on the block.