Texting an American, as I well knew, is only marginally more effective than attaching your message to the back of a baffled city pigeon. Americans simply don’t do texting.

So, what is the couchsurfing etiquette? “We’re super-flexible, but there are a few rules,” says Elizabeth. “We want surfers to be comfortable, but not too comfortable. It’s nice when there’s a gesture, like bringing us a gift from your home country, or taking us out to dinner.

“And staying two or three nights is cool; longer gets a bit awkward. We do get the eccentrics, of course, like the Austrian couple who said they were travelling to help each other through depression, then vomited out their entire life stories in 90 minutes. But mostly, it’s positive.”

What’s in it for Elizabeth and Alex? “Well, it’s always cool to meet people, especially Europeans — we see enough of Americans. And we’re hoping to go travelling next year, touring all of our couchsurfers.”

On the other side of the Atlantic, Jane and Phil Ballard of Ely, Cambridgeshire, also offered themselves as hosts in the hope of meeting “a few interesting souls”, but their experience was less positive. “We put up various surfers,” says Jane, 55, “and worked hard to give them a good time.

Some asked us to visit them (and some even meant it), and we have a gaudy collection of photographic calendars and plastic dolls to show for their visits. Then we had a bad experience with an American. She persuaded us to delay our own holiday to accommodate her, told us her time of arrival at the station and then failed to turn up.

She e-mailed a week later, saying she’d felt ‘a bit tired’ and had decided to stay in London. That did it for me.”

For the couchsurfing newbie, navigating the website in search of a potential couch can also be a darkly unpredictable business — profiles of seedy-looking, bare-chested gents go unpoliced, and introductory straplines such as “I have the ability to synthesise some compounds and I can separate drugs from bile, plasma and urine” can do unfortunate things to the browser’s own bile.

But the couchsurfing site does offer some safeguards, such as a system (similar to eBay’s) of users vouching for each other online and a higher verification level (for £13), where a letter is sent to the host’s home address requiring a postal reply.

The site also makes an effort to lessen the risk of surfing mishaps with its stern admonitions to book a hotel as backup and to avoid staying with unverified members or lone males if you’re a single female traveller.

None of this dissuades a growing number of Elizabeths and Alexes, though: “Even if you did end up peeing on the rug, I doubt I’ll be put off,” smiles Elizabeth. “The beauty of sites such as this is that they make the web world real, and make us take a leap of faith — you’re rewarded in finding out that human beings are generally a pretty cool bunch.”

www.couchsurfing.com A professional-looking site, with numerous functions, thataims to “create deep and meaningful connections that cross oceans, continents and cultures”.

www.globalfreeloaders.com An Australian hospitality network, with the antipodes particularly well represented.

www.hospitalityclub.org One of the web originals, aiming to “bring people together”. Duration of stay and specifics (such as food) are set out before your stay.

www.stay4free.com A global “free accommodation network” based in Holland.

www.travelhoo.com Another of the early web outfits. Also offers a travel partner-finding service. Sign up to surf

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