SIMON CALDER

Yum. Eat a Bounty bar, book a holiday and earn pounds 50 in the foreign currency of your choice. This is the offer that Mars and Airtours have put together. Unlike all the other discount deals floating around, no strings appears to be attached. You buy your Bounty, send in the wrapper, go to Going Places (Airtours' own travel agent) and book. No mandatory insurance, no minimum spend.

This offer runs for bookings made until the end of the year. So try this trick: wait until next summer's holidays are launched (which could be as early as July this year) and use the voucher for one of the loss leaders that the tour operators roll out in order to put "Holidays from pounds 99" on the front of the brochure. With a bit of luck, a trip for pounds 49 could be in the offing. The last deal I saw as good as this was offering free flights to America courtesy of Hoover.

One last tip: the outside of the wrappers says "send in two proofs of purchase", but inside only one is mentioned. The company says people sending in one will qualify.

This bounteous offer is more generous than the one promoted by the makers of Aero (it's tough work, you know, researching all these chocolate stories). If you take up their invitation to "float away to paradise", you could find yourself spending pounds 108 to save pounds 100.

Munch your way through four Aero bars, and you can save pounds 100 on a holiday - but only if you choose one costing more than pounds 700. If this is for two people travelling together, you must each buy insurance, costing pounds 54 for a fortnight. By comparison, the Independent's annual travel policy (available on 0800 551881) costs pounds 78.50 for a whole year.

Tourists are more sophisticated than the travel industry assumes. We caught up a long time ago with the tired old trick of using overpriced insurance to fund discount offers. The cumulative effect is to make us deeply suspicious of any promotions offered by travel agents and tour operators, and to realise that Aero bars can end up costing considerably more than 27 pence.