== "ersatzgiver"? == 

 Judging by the sources given, this neologism seems to be restricted to a very specific context ("The Freecycle Network") and ununderstandable without that context, because it is derived from another word ersatzfriend that isn't in use elsewhere. Ersatz in English means a cheap, unsatisfying surrogate for something (ersatz coffee), not a trade-in. The google hits I checked refer to TFN or this article. Unless this term has been adopted outside the TFN context, I don't think it is notable. Wikipedia shouldn't be a vehicle to introduce new words.