Abebooks.com lets you search and shop from the stocks of 13,500 booksellers worldwide. You can find readable used paperback editions of most popular titles for 59p, plus postage and packing. Interesting options include a signed copy of The Razor's Edge by Somerset Maugham for £9.

Play.com offers a vast range of entertainment products that overlaps with Amazon's, but with more emphasis on DVDs, CDs and video games. Bargains include the film Pretty Woman and the album The Best of Groove Armada, both at £2.99, including postage. Users can sign up to PlayTrade to sell used items to other customers, paying commission of 10 per cent plus 50p per sale.

Firebox.com sells “gadgets, gifts and boys' toys”, with plenty of interesting options for less than £20. Offerings include a palm-sized radio-controlled helicopter for £19.95 and vodka-flavoured lollipops that contain real Chinese scorpions - said to be a potent aphrodisiac - at £3.95 each. Meanwhile, the Etch-A-Sketch (£12.95), Guess Who? board game (£9.95) and Sesame Street dolls (from £12.95) all give a retro flavour.

Koodos.com offers discounted designer gear. Good deals include G-Star lumber jeans for men at £49.99 (down from a recommended retail price of £89.99) and a women's Prada shopper bag at £399 (down from £600).

Asos.com/red also offers discounted women's clothes from brands including French Connection and Junk Food - the latter worn by Paris Hilton and Mischa Barton. T-shirts from the Los Angeles label start at £15, down from £40. A leather jacket from Roberto Cavalli's Just Cavalli line is listed at £200, down from £500.

Lastseason.com does what the name suggests, selling slightly older stock from clothes labels including Diesel and Bench at knockdown prices under the slogan “quality never dates”. One example: Light blue Diesel Wonnha jeans for women at £19.99, down from £139.99.

Amazon.co.uk is most associated with books, but sells electronics, clothes and household goods, too. “Deals of the week” in the latter category included a Kenwood Chef KM010 food mixer at £199.99, down from £399.99. The same mixer costs £329 at Johnlewis.com. User reviews and star-ratings are a helpful feature.

eBay.co.uk, the auction website, is the country's best-known trading portal, with people routinely vowing to “eBay” unwanted presents. You can buy or sell almost anything legal at the site, from vinyl to cookbooks.

Myvouchercodes.co.uk lists promotional codes that give discounts at online retailers. Click on the “most popular” tab for the hottest deals - at the time of writing these included 20 per cent off at Asos and 20 per cent off at Littlewoods on orders of more than £75. Note, however, that the codes listed may have expired by the time you attempt to use them.

Madaboutbargains.co.uk lists sales and offers across the web, as submitted by users. At the time of writing, recent notices pointed to a half-price toy sale at Woolworths.co.uk - a Bratz doll, for example, was reduced from £19.99 to £9.99 - and a three-for-two offer on Christmas gifts at Marksandspencer.com.

Despite soaring food costs and energy bills, the prices of many items are actually falling - especially electronics and white goods. Below are the ten categories in which costs have tumbled the most in the past year, with examples of one big-selling product in each.

1 Speakers: down 57%. Logitech MM50 portable iPod Speakers, down 70%. September 2007: £119. September 2008: £35.99

2 Mobile phones: down 53%. LG Viewty KU990 mobile handset, down 54%. September 2007: £350. September 2008: £159.99

3 Camcorders: down 43%. Panasonic VDRD100b DVD camcorder down 46%. September 2007: £285. September 2008: £153.85

4 Digital cameras: down 40%. Canon Digital Ixus 960IS 12.1MP digital camera down 31%. September 2007: £360 September 2008: £248.88

5 Flat-screen TVs: down 33%. Philips 42PFL5522D 42in HD-ready LCD TV down 33%. September 2007: £750 September 2008: £499

6 Microwaves: down 28%. Sharp R959SLM combination microwave down 30%. September 2007: £223 September 2008: £153.99

7 Games consoles: down 25%. Microsoft Xbox 360 Elite Console down 27%. September 2007: £300 September 2008: £219.95

8 Washing machines: down 22%. Bosch WAE28363GB 1400 spin washer down 30%. September 2007: £450 September 2008: £317

9 MP3 players: down 21%. Apple iPod nano 8GB down 13%. September 2007: £125 September 2008: £109

10 Fridges: down 10%. Electrolux ENN28600 built-in integrated frost-free fridge down 12%. September 2007: £552 September 2008: £490

Source: Kelkoo.co.uk