It is a geekfest. That is to say, it is the annual conference for computer trainers. I'm not your average IT professional. I'm the wrong side of fifty, I'm married with kids, and I don't rank Star Trek in my top ten films of all time. Well, maybe that one film they did for laughs, but I definitely don't speak Klingon.

So here I sit, ensconced in one of those armchairs that look really comfortable until you actually sit in one, trying to look as though I prefer my own company.

Hotel lobbies are great places to people-watch. My fellow nerds are obvious. They display their electronics like peacocks, their manhood in inverse proportion to the size of their gizmos. A few group together, bonding over the latest interface. Others sit in islands of awkward isolation, jaws dropping whenever one of the rare nerdettes walk past, shamelessly flaunting her electric-pink Blackberry.

Oh God. I have died and this is my punishment. If I sinned that much, how come I don't remember enjoying it?

"Bob!"

The voice carries across the lobby. It is an American voice, and the Georgian drawl makes it sound as though I am a fishing hook: Barb. People look up. Females are rare in this environment, but it wouldn't have made any difference if we were at a Women's Institute meeting. Claudia has a voice that commands attention.

I look up and smile in what I hope is a warm way. I'm not cold, you understand, just English. Sorry. Claudia, in comparison, beams. I rise, and she pulls me into her orbit, my moon to her sun.

"Barb, how are you?" she calls, still five metres away, but closing.

The English are so bad at this. 'How do you do?' we ask, never once asking ourselves, how do we do what? Never really caring about the answer. 'Not too bad,' we reply, even if we have all four limbs in plaster, because we know the enquirer would curl up in embarrassment if we actually answered the question honestly.

Claudia is different. She asks with all the sincerity of a nun at an orphanage. Her beaming face, her body language, the tone of voice, all cry out that she absolutely, genuinely needs to know how you are. You can't help yourself, to deny her this vital information would be like denying a puppy water.

"I'm all the better for seeing you, of course."

Her face flares. It is a stock pleasantry I say to everyone, but she chooses to believe it, and delights in it. Her sun flare interferes with my communication systems, I feel my witty banter dry up, and I am drawn into her gravity well by the sheer warmth of her greeting.

"Oh, I bet you say that to all the girls."

I look around at all the hundreds of women queuing up to greet me. Yes, being English means I'm sarcastic too.

"Yes, but I only mean it when I say it to you," I reply.

She laughs, and my spirit soars. Making Claudia laugh is like shining a flashlight at the sun, but you feel special anyway.

I give her a hug, awkward and shy. We'd only met once, briefly, a year ago. Apart from that, our relationship blossomed over the Internet. Online I am flirty, witty and gorgeous. Which is easy, when you have a day or two to think up your next off-the-cuff post. It's scary, meeting a virtual sparring partner in real life. Will I be a disappointment? And what are the rules about greeting? A handshake was far too formal for all the years we had virtually known each other, a kiss too presumptuous.

"How are you, how's the family? So what did you have to promise Jacqui to let you out on your own? Oh, how did the wedding go? Is your daughter's poor husband still frightened of you?"

The questions tumble out of her like a waterfall, the next one cascading down before the previous one has landed. I'm a good forty centimetres taller than her, but I feel dwarfed.

"Fine, fine, hot rampant sex, fine and of course," I tick the answers off on my fingers.

"Oh my, oh my!" she said, fanning herself with her hand. "I'm going to have to sit down. All I heard there was hot sex, and the rest just flew out the window."

Sitting down, she is no smaller. She leans forward, and I am humbled to be included into her personal space. The fact that her personal space seems to extend ten metres from her body makes me feel no less privileged, for I am the centre of her attention.

"You know, one day I'll just have to meet that long-suffering wife of yours and compare notes. I'm sure she has no idea how you talk about her behind her back."

"Funnily enough, she says she can't wait to meet you. Mind you, she says it through gritted teeth and smacks her fist into her palm as she says it."

She laughs again, and, yes, it was me that made her laugh. I bathe in the warmth.

"Oh, right. Like she has anything to fear from me. You've got 'happily married' stamped all over you. You look after her, you hear? She's got enough to put up with, being married to you and all."

"Thank you ... um ... I think."

"Oh, listen to me," she says, swatting the idea from the air. "Giving out marriage advice like I know."

"Hey, I'm sure we could sort you out with someone this week. Some of these guys must be single. Virgins, even. Can you speak Klingon?" I make as if to attract the attention of any single nerds in the vicinity. A passing waiter stops, misinterpreting my actions.

"Oh, that's a good idea. Do you speak English?" she asks.

"Yes, madam," replies the waiter, with less of an accent than Claudia.

"Do you do cappuccinos here?"

"Of course."

I am struck by her contradictions. At face value she epitomises what we always think an American tourist is like. She is loud: loud clothes, loud voice and loud personality. You can't ignore Claudia. But with that brashness comes a lack of conceit. Some Americans carry America around with them. The rest of the world is just America with an accent. I remember once being asked by an earnest American how we celebrate Thanksgiving in the UK. But Claudia didn't assume everyone spoke English, or knew what pastrami on rye was, or even assume that a large Berlin hotel would serve cappuccino. I find myself unconsciously following her lead.

"Do you serve Earl Grey?" (What? Had you forgotten I'm English?)

"Yes, sir."

"Aren't the people here friendly?" she asks, as the waiter leaves. "People say the Germans are cold, but every single one of them has been so helpful to me, I can scarce believe it."

I wonder how anyone would dare to be unfriendly to Claudia. I wonder how anyone could even think it. She throws herself onto you open-armed, metaphorically speaking. The sort of person that could be unfriendly to her would be the sort of person that could kick kittens.

"You do know that the waiters here are paid to be friendly to guests?"

Her easy laughter dismisses such a preposterous idea. "Oh, now you're just being mean. I'm sure he's a lovely boy." And I'm sure, even if he had sold his own grandma, he would be lovely for Claudia.

The next hour passes like a minute. I am no longer dreading the week. How could I? We laugh and gossip like old friends. Because, surely, everyone she meets is an old friend within minutes. And the rubber band that I keep continually wound (because I am English, after all) slowly unwinds. I ignore the looks people give us, the odd couple: reserved Brit and loud Yank (and I laugh internally at calling this Southern Belle a Yank, though I not dare call her one to her face). I drop my guard; it's not needed. I ask her questions I genuinely want to know the answer to, not just out of politeness.

And when it's time to go to the conference hall, I follow her comet tail, content to be in her universe.