Iwill forgive you if you haven't noticed, but every US state has now legalised home brewing.

The Prohibition era ban was lifted in 1978, although individual states could choose whether to allow brewing at home. Mississippi became the last to lift the restriction on July 1.

According to Scott Williams, of the Williams Brothers microbrewery in Alloa, the whole craft beer revolution that blew in from the States began when American home brewers discovered there was more to life than Budweiser.

The powers that be have never banned home brewing here, or found ways to tax it which explains why home brew is so deliciously cheap. In these straitened times, with beer taxed as never before, the band of amateur brewers is beginning to swell. Their numbers had been relatively stable after a big spike in the 1970s. In Edinburgh their needs were met through mail order and two small shops. Tucked down a Leith side street for 35 years, Edina Homebrew was run as a hobby by David Martin, a retired antiques dealer, until his daughter Shirley Easson took over. A week before Christmas she moved it into a comparatively huge, double-fronted shop in the centre of town (61 South Clerk Street). Open 7 days a week, it's now called the Brewstore and Easson has barely drawn breath.

"Beer-making has become incredibly trendy. It's the new rock 'n' roll," she tells me, pointing out bins of vacuum-packed hops from all over the world, and bags of roasted malt in every shade of colour. The malt is freshly ground in a coffee grinder for anyone preparing to make a brew. For beginners there are beer kits from £60 which include all you need to make everything from the palest pilsners to the darkest stouts. These kits are miles better than the 1970s prototypes, and are more or less idiot-proof (even I managed to do it).

From there you can progress to "extract brewing" which requires a large pot and a little more knowledge, as you add in the hops yourself and any additional flavours such as elderflower. For Easson: "It's like making soup - anyone can do it."

Then, having gained sufficient confidence, you can plunge into the world of "all-grain brewing", which is what commercial brewers do every day. The only difference is that of scale and the fact, already mentioned, that the Government receives not a penny in tax. "I suppose they could tax yeast," I suggest to David Martin, who happens to be in the shop that day.

"Shhh!" he says, with a finger to his lips and a look of horror. Somehow I can't see it happening, or any attempt to regulate home brewing. The thought of excise men prowling the streets, sniffing the air for the scent of an illicit brew, seems most unlikely.

The prospect of cheap, duty-free beer is undoubtedly the main draw for most people, but the sense of creativity and fun soon overtake considerations of cost. To encourage people to give it a try, Brewstore is launching Britain's first home brewing school next month - introductory courses will be about £45. (www.brewstore.co.uk). Meanwhile the Williams Brothers' home brew shop in Glasgow - Glen Brew (www.innhousebrewery.co.uk), is as busy as ever.

This Saturday you can taste Brewstore's Black Heart IPA among a hundred beers at Great Grog's Beer Fair (Edinburgh's Café Camino 1, Little King Street, 6pm) .