The brasserie in the National Gallery's Sainsbury Wing is their favourite virtual office. "It's air-conditioned, spacious, comfortable and rarely busy in the morning," says Landy. "Our virtual office may have cost a few million pounds to build, but we use the facilities for the price of a cup of coffee and the occasional Danish pastry." Landy confirms meetings on a postcard from the gallery.
Mindworks once leased a suite of offices in Bloomsbury costing several thousand a year. Now they use a serviced office (also in Bloomsbury) to take phone calls and post. For meetings, they pick venues to suit clients. The National Gallery is convenient for their Whitehall-based public-sector clients. For meetings with private companies, they have convened at the cafes in the Festival Hall, on river boats on the Thames, and they have even travelled to Paris on the Eurostar, working on the train and over lunch at the Louvre.
Cooper believes organisations are still quite conservative in their attitudes to home-based businesses.
"There are many misconceptions about working from home," says Cooper. "People think it means working at home, but of course it doesn't. Very few people could work entirely at home."
Devoting attention to the right venue is as important as if you were renting an office. For Caroline Blunden, a specialist in contemporary Chinese painting, ambience is important because she frequently entertains visiting Chinese artists. "I choose places which are informal and where the artists can do a bit of sightseeing at the same time,." she says.
Blunden is a regular at the Design Museum cafe and at the South Bank Centre, which provide "great views of the Tower and the Houses of Parliament".
Blunden splits her working day between home in Battersea, the Alan Baxter Gallery in Clerkenwell - where she is currently exhibiting around a dozen Chinese artists - and her virtual offices. For corporate clients who view the exhibition in private she will talk finance afterwards in one of Smithfield's cafes or fish restaurants.
Most cafes at galleries and concert halls are happy to become offices, as long as customers keep buying refreshments. A table of businessmen drinking one cup of coffee an hour does not make financial sense when tired and parched gallery-goers are queuing up outside.
"We are very happy to be a venue for business meetings," says Mike Rickard, general manager of the brasserie at the Sainsbury Wing. "We have no music, the atmosphere is subtle and people can talk undisturbed. The tables are big and we see lots of PCs, mobile phones and briefcases coming out."
Far less discreet in tone are the string of Aroma cafes which have sprung up around London. They have a motto: "15 minutes of sunshine," and pulse to Latin American samba as customers soak up the Mediterranean oranges, aquamarines and ochres of the decor. Coffee is their speciality and comes frothed, whipped, iced, decaffeinated and flavoured.
"The idea is to come off the streets of London and have a 15-minute holiday," says David Carter, manager of the Bishopsgate branch of Aroma.
Customers include employment agencies conducting job interviews, fashion companies with portfolios and City workers holding meetings away from the formality of the office. According to Neil Dookun, the company's operations manager, "Aroma is a great place to be seen, we're very vibrant, very lifestyle, and we're riding on the back of a trend."
Many organisations are now peopled by homeworkers, freelancers and consultants. A company's clients, in fact, are likely to be equally office-less.
Jonathan Theobald, a video director/producer, runs his company Country Films from his Wimbledon home. "The video industry is full of freelancers," he says.
"I think people feel uncomfortable holding meetings in their own homes. It is difficult for both the company and client with interruptions from spouses, pets and children."
Recently he organised a meeting in the Langham Hilton Hotel, north of Oxford Circus. His client was based in Hereford and the public relations people came from Shropshire. Both were visiting London on business anyway. "I chose a central place and we sat in the bar and drank coffee," says Theobald. "I don't need to rent an office and the meeting cost me three cups of coffee."