There is little more stressful than a supermarket on a Saturday. Parents pilot overloaded trollies through heaving aisles while bored children create chaos. The staff are in overdrive to keep shelves stacked and quick-shop singles huff and puff with indignation.
By comparison, hooking up to the internet, sending a shopping list across cyberspace and sitting back waiting for a happy chappy to deliver the lot, professionally packed, to the front door, seems like heaven.
This is the world of online grocery shopping, where you let your fingers do the walking and use your modem, not your muscles.
It is also a business where Britain is leading the world. A higher proportion of British food shoppers have converted to the net than in any other country and Tesco.com is now the world's biggest internet grocery business.
According to market research group Datamonitor, British grocery shoppers spent £395m online last year - with more than half of that ending up in Tesco's tills.
But in terms of the £95bn UK grocery market, it is still a tiny business - accounting for just 0.4% of the market.
Datamonitor believes online shopping will account for 5.4% of the British grocery market by 2005. Across Europe, they calculate, the market share is likely to be only about 3%.
Investment bank Goldman Sachs estimates that e-tailing groceries is likely to grow to 7-10% of the European market in the same period. The Institute of Grocery Distribution, however, believes that 23-27% of the grocery market will be online by 2008.
The variations are huge, but the market for groceries is so vast that even the most conservative estimates would create a substantial business.
So far e-grocery firms come in two forms: pureplays, which are new businesses set up specifically to deliver groceries to the customer's door, and traditional supermarkets exploiting a new sales channel.
Pureplays have dominated in the US, where for a while they were among the brightest stars of the dot.com share boom. Webvan launched on the US stock market in 1999 backed by an impressive list of blue-chip investors and banks.
Its shares have crashed so low, however, that the company could be thrown off the Nasdaq - and it has ceded important markets to US grocers.
Earlier this week, Webvan pulled out of Dallas saying it had trouble competing with GroceryWorks.com, a small online grocer owned by Safeway, and with other brick-and-mortar companies such as Wal-Mart that offered unbeatable prices.
In Britain - and now in the United States - it is traditional supermarkets that are setting the pace, led by Tesco.com. Online grocers have used two distinct business models - either using warehouse "picking centres" to fulfil orders or simply sending staff up and down the aisles of existing stores. The pureplays, together with Sainsburys and Asda in Britain, set about building specialist low-cost picking centres, while Tesco based its service on its stores.
It was a smart move by Tesco. It may not be the most efficient model in the long term, but using existing stores and staff meant Tesco was able to roll out its service cheaply and rapidly - and steal a march on its rivals.
In the five years since Tesco.com was launched it has grown from a pilot project in 11 stores to a service available in nearly 250 of its outlets. It covers 90% of the population and has 750,000 registered users who place 60,000 orders a week.
Tesco has invested £60m in the service, buying hundreds of vans and installing computer systems - and claims its new way to do the weekly shop has also created 8,500 jobs.
Left behind in the race to win customers, Sainsbury's and Asda have been forced into a rethink and are playing catch-up by rolling out store-based services to supplement their picking centres.
"The store operation allows us to roll out rapidly, to assess and build demand in new areas without the greater investment of picking centres," Sainsbury now says, belatedly. Even so, Sainsbury's still only covers about half the country while Asda can only service web shoppers inside the M25 plus a few more outlying home counties towns.
Iceland - which changed its name to Iceland.co.uk to reflect its online creden tials - is also sizeable player in the market, although several others, such as Somerfield and Budgen, have recently logged off, having failed to build a big enough customer base.
About 65% of online grocery shoppers are women - but the key to running a successful online grocer is size. To be profitable they need a lot of big-ticket, busy family shoppers, who regularly spend more than in-store shoppers.
The average Tesco.com basket size is £85, four times the in-store average. But the grocer needs to ensure that shoppers are buying the full range of goods. According to one supermarket executive, shoppers buy more low-margin bulk and commodity items online, such as toilet rolls and tinned beans. Tesco is addressing that problem by offering more non-food lines, including furnishings, electrical goods, videos and clothing on its website.
The grocers must also generate regular business. With 60,000 orders a week, most of Tesco's 750,000 "registered users" are not regular users. Webvan in the US has the same problem, but magnified. In San Francisco - its longest established market - its shoppers order only 1.8 times a quarter.
Datamonitor believes that online grocery shopping "is set to become the largest business-to-consumer sector given that expenditure on food, drink and household products is still the most important element of consumer expenditure after housing costs". They calculate that the market is worth $3.5bn (£2.6bn), but will be worth $55bn within five years - a compound growth rate of more than 77%.
Britain, they say, is leading the field because British shoppers are much more relaxed about giving out their credit card details to make purchases on the phone - and are therefore less concerned about security risks when making purchases.
Elsewhere in Europe, e-tailing is most advanced in the Netherlands, where the Ahold chain last year bailed out the struggling US web grocer Peapod.
Virtual chains
Leading online grocers sales 2000
Tesco, UK £210m
Ahold (inc Peapod), US & Holland £116m
Webvan (Inc Homegrocer, US) £85m
J Sainsbury, UK £42m
GroceryWorks, US £41m
Asda Wal-Mart, UK £35m
Homeruns, US £34m
Albertson's, US £24m
Iceland, UK £22m
Carrefour, France £21m
Galeries Lafayette, France £21m
Groupe Casino, France £17m
Waitrose, UK £16m
Cora, France £15m
Source: Datamonitor analysis
