Ebay (in the UK) have set up a special "Charity Auction" area which is dedicated at the moment to "Children In Need". As far as I am aware give you special reduced rates and they donate all associated listings fees on your behalf.
I think at the moment it is only for Children In Need, but after the event in November they will be opening it up so that anyone collecting for any registered charity can use the service.
Check out this link for more info: http://pages.ebay.co.uk/community/charity/index.html
Ian
