i keep trying to get my head around the exchange thing but haven't quite mastered it yet...
i tend to sell the big things there, like master keys and stuff, but haven't bothered looking into actually selling anything else there...
I sell most excess items that the DOFF assignments give me and it provides my characters with a moderate cash flow.
I started the Caitian refugee assignment the other day. I need to check the results of that.
IMHO, it was mainly the younger crowd booing at the Excelsior. You know the ones that grew up watching TNG with the Galaxy class.