LootList

LootList gives you your own online storefront where you can easily list any in-game items you're trying to sell (think MMOs, loot-driven ARPGs like Diablo, etc). Essentially a free web page to put your loot. You can share your storefront/listings, or just use it as an inventory management tool. Works with any game.

It also integrates with Discord messaging. Anyone who sees your listing can click "Message on Discord" and they'll be instantly (and I mean instantly! :) ) connected with you in a private messaging thread on Discord.