we like to stock up with charity pin badge's such as the RSPB ones found here http://www.ebay.co.uk/sch/rspb/m.html?_nkw=&_armrs=1&_from=&_ipg=&_trksid=p3686 normally around £1 each, that way we are donating to charity whilst getting our geocaching swag. Have also in the past found caches and all ive had is unscratched lottery scratchcards with me so have left one of them. never heard back from anyone saying they have found a winning one yet.