In a very similar vein:
Have you read Robert McLiam Wilson's Eureka Street? made into a mini series in 1999 by the BBC.
Main character Chuckie Lurgan makes his fortune by advertising giant dildos for sale in his local paper. Gets sent lots and lots of cheques as payment. Waits for cheques to clear then mails out refund cheques with "Giant Massive Dildo Refund" stamped in big letters on the cheques. Needless to say the cheques aren't cashed and he makes a fortune... tempting