Ghengis, The glider pilots' exemption from radio licences dates back to when glider radios were single channel or only very few fixed channels, dedicated to gliding and no other users - a bit like CB for which operators' licences were/are not required (still true?), and like unlicensed operators can today use radio telephones (i.e. mobiles) and certain other equipment with dedicated channels. The last generation of those gliding radios were the Pye Bantams etc., hard-wired using crystals. If any remain in use, they are still restricted to gliding channels only and should never interact with other frequencies.
Operators' licences are of course needed for use of other aviation channels, and for use of radios with capability of changing to non-gliding frequencies (so even a Pye Bantam if any of its crystals was for a non-gliding frequency). All modern radios AFAIAA need operators' licences, simply because they are multichannel.
Windrusher, good point about the advice re aerodromes with IAP's - I bet most people don't know that, and of course it is not mandatory. But commonsense should deter people from circling 5 miles out on an IA - unfortunately the problems, as so often in aviation, are caused by people lacking in that commodity.
The flight I referred to was 347km (in a Ka6E) - I don't think 500 was on that day in wood.