It's 7.30am on a fresh summer's day, and I find myself gazing at a canvas that appears to show a collection of rose-coloured penises struggling to get out of a nest. Behind this arresting image, a single wisdom tooth, bound by string, is spinning within a small motorised cage hung about with knots of hair. It could only be the Royal College of Art's annual graduate show. The RCA's affable rector, Christopher Frayling, stands beside a table of bagels, welcoming everyone in. He tells me that his younger bro is also a rector, but of the lesser C of E strain.

"The academic type came before the religious one," he observes. Yet isn't his role similarly paternal in manner? "Oh yes. We look after the students, hear their boyfriend/girlfriend problems," he sighs. What? The famously confident RCA students behave as if Frayling were a latter-day Irma Kurtz? "Hmm," nods the rector. "Of course, many of them go on to be frightfully famous. I mean, when she was here, who would have thought Tracey Emin would get anywhere?"

Indeed. This year, many of the students have taken up positions next to their art, presumably to help you work out what's going on. Sadly, or maybe mercifully, the "penis nest" artist is absent. But in the basement, at Ceramics and Glass, I am intrigued by a pair of cups and saucers decorated with a subtle ripple effect. Suddenly the artist responsible, Geoffrey Mann, is by my elbow. "It's the effect of breath," he explains. "I took digital photographs of what happens when you blow on a cup of tea, and integrated the waves on to an actual piece of ceramic." He has extended the idea to lights, solidifying the waves caused by a moth darting around a naked light bulb. I tell him I could see his cups and saucers going down well at Habitat. Mann looks at me warily. "I'm actually thinking of continuing with my digital research," he explains. "At MIT or somewhere in the States."

This is not to say that RCA students, who are offered a course on how to attract an agent, don't have a very clear idea of how to market their work. In the Goldsmithing, Silversmithing, Metalwork and Jewellery section, Nanna Beckmann Jensen is presiding over an array of products that would not look out of place in Selfridges, and will quite likely end up there. Dressing gowns made out of blankets, a funky foot exerciser to avoid deep-vein thrombosis when on your computer, and a rubber lemon-squeezer that has already been prototyped for commercial sale - these are all part of Jensen's oeuvre, as is a range of cups and saucers decorated with nipples.

Jensen, who is Danish, thought it was hilarious when she discovered that we Brits talk about "cup size" when discussing our Triumphs and Maidenforms, or equivalent. So she designed a series of ceramic cups and saucers with bras very much in mind. I pick up one that has got to be a double D. "Oh yes, I have done Breakfast Tea size, Cappuccino and Espresso," laughs Jensen, who clearly thinks British bra terminology is like something out of a 1950s comedy, perhaps set at the Wedgwood Potteries with Babs Windsor. Carry on Ceramics. "At first sight, you see a normal cup. It's only when you pick it up and see the nipple protruding from underneath that you realise it's something quite different," she kindly explains. So saucy. Or should that be saucer?