John Lennon's cheque to the taxman is bouncing round the auctions while diminishing in value. Made out for pounds 912 and dated 16 May, 1969, it failed to sell at Phillips two years ago (estimate pounds 1,800-pounds 2,000), where it had been sent by a collector who had paid pounds 2,500 for it. It bounces into Bonhams Chelsea's rock and pop sale on Thursday (12 noon) with the same optimism, pounds 1,800-pounds 2,000.

The taxman did succeed in cashing it. Then, filed away at the District Bank, it acquired a value as pop memorabilia. It is not the first of Lennon's renderings to the taxman to be sold at auction. His payment of pounds 14,483, dated December 1971, sold for pounds 550 at Christie's South Kensington two years ago. How do Lennon cheques escape from banks? The theory is that sharp-eyed clerks pilfer them when they should be shredding them.

John Crittle, Lennon's tailor, made him a special black gaberdine jacket for his appearance in court for cannabis possession. It is est pounds 12,000- pounds 14,000 in the sale. Freddie Mercury's black Japanese kimono with dragons and lightning is est pounds 2,000-pounds 3,000. The sale offers yet another instalment of Mercury's impassioned scribblings to his lover, David Minns. On Minns's notepaper, Mercury pencilled a spiral doodle and wrote "Minsy is a Trollop!" (pounds 500-pounds 600), on another sheet he illustrated his observations of Mr Minns, "You Fat Pudding!" and "You Ol Tart!" (also pounds 500-pounds 600).

Prices for paintings by the "fifth Beatle", the late Stuart Sutcliffe, Lennon's contemporary at Liverpool College of Art, are going up. He was probably a better artist than a musician. His The Dustbinmen, a thickly- painted street scene, was discovered in a cupboard in the college. Est pounds 4,000-pounds 5,000.

Bonhams Chelsea scored a hit in March with its first sale of Sixties psychedelic and underground posters: 95 per cent sold by value. A UFO Dusk to Dawn concert poster fetched pounds 713, five times est. About 270 more from ageing hippies' attics are in the second sale, Wednesday (12 noon). A multi-coloured poster that launched the first issue of the seditious magazine, Oz, is est pounds 200-pounds 300.

Bonhams's sporting sale, Thursday (11am), will show that prices for football memorabilia are rising as fast as golf and cricket - though they are unlikely to catch up. At Bonhams Honiton this year, a husband bidding for household furniture with his wife saw the earliest Aston Villa football programme of 1902 and successfully bid pounds 1,100 for it.

In Thursday's sale, the earliest known FA Cup Final Programme of 1889 is est pounds 3,000-pounds 4,000. A 1921 FA Cup Final Programme from Arthur Grimsdell, who captained Spurs to victory in the game, is pounds 300-pounds 400. Prices have doubled in the past two years.

Part Two of the sale offers sporting guns, cased fish and fishing tackle, Tuesday (11am).

Montague Dawson's sea paintings, in the pounds 10,000-pounds 15,000 bracket two years ago, now fetch pounds 20,000-pounds 25,000. In January, one fetched pounds 51,700 at Bonhams' biannual marine sale, which casts off again on Thursday (11am) with a Dawson est at pounds 18,000-pounds 25,000.