A bit ago, we discussed this (in Thoughts on a community "Marketplace" section?) and decided that we should perform the experiment to see if there's much demand for people buying/selling equipment.
I've not seen a lot of subsequent traffic, so go ahead and post your equipment (subject line can be something like, "For Sale: XXX Router...") and provide a good description. I'd post in the "Installing and Using LEDE" category, since that gets the most traffic/eyeballs.