A British student, Dean Robinson, has been barred from E-Bay for the following infraction:

Your listing breached eBay’s No Item policy and has been removed …
You may not list intangible items or items whose existence cannot be
verified, such as ghosts, souls or spirits.

Robinson’s listing offered unspecified services in return for financial support to enable him to attend Cambridge.  He condemned the ban as "completely pedantic," but

Ebay denied it was a spoilsport, claiming Robinson’s offer was too vague. Vanessa
Canzini, a spokeswoman, said: ‘In the listing he talks about
"sponsorship" and "employ" which would have hit our keywords for
spamming. He also uses words like "negotiable" and "rates", so you
wonder what is this guy offering? I suggest he looks at the email we’ve
sent him. His listing is all over the place. He needs to be clearer
what the buyer could expect.’

She pointed to the example of
Nicael Holt, an Australian student who earlier this year auctioned his
life on eBay, offering his name, phone number, worldly possessions and
circle of friends to the highest bidder. Bidding was permitted because eBay deemed the listing to be sufficiently detailed and tangible. It closed at $A7,500 (£3,114).

Details courtesy the Guardian, here.