A mention on Watchdog of a product we've helped create (and continue to promote) isn't something we'd normally want to shout about, but BBC One's influential consumer advice programme last night recommended the Kalixa prepaid MasterCard as a way to avoid Ryanair booking fees.

Guest presenter Martin Lewis, from the UK's official No.1 money site MoneySavingExpert.com, reported on the exorbitant booking fees charged to travellers looking for cut-rate air fares. Budget airline Ryanair, for example, charges an "administration fee" fee of £6 per person each way, meaning a family of four gets stung for an additional £48 on top of the cost of tickets, purely for the privilege of paying by card - which, when making online purchases, is generally difficult to avoid.

Lewis's report revealed that the additional - and seemingly unavoidable - card booking fees charged by the budget airlines bear little relation to the actual processing costs incurred by the companies. Michelle Whiteman from The UK Cards Association explained that a Merchant Fee of around 1.5% - 3% of the total transaction cost is charged to a retailer when accepting a payment by credit card, and the charge for accepting a payment by debit card is just "pence".

According to Lewis, the budget airlines can only advertise their rock-bottom ticket prices without factoring in booking fees because they consider the option to pay by credit or debit card to be an "added extra". But to be able to get away with this, the airlines need a "way out", offering at least one payment method that incurs no additional charge or administration fee.

After the report, in discussion with Watchdog host Anne Robinson, Lewis explained that Ryanair's "way out" is a MasterCard prepaid card, citing Kalixa as an example.

• Watch the full report and discussion between Martin Lewis and Anne Robinson (available on the BBC iPlayer until 8:59pm on Thursday 21st April 2011)
• See what Martin Lewis says about Kalixa on MoneySavingsExpert.com