Currency Vendor Recipes:
6 Linked Item: Sell a 6-link item (with six linked sockets) to a vendor for 20 Orbs of Fusing.
Full Set of Rare Items: Selling a full set of Path of exile currency rare items (one of each slot: helmet, boots, gloves, etc.) will give you a Chaos Orb or an Orb of Alchemy, depending on the item levels.
Unique Item Vendor Recipes:
Cartographer’s Chisel: Selling a Stone Hammer or Rock Breaker with 20% quality and any Map will yield 1 Cartographer's Chisel.
Glassblower's Bauble: Selling 20% quality flasks (totaling 40%) will reward you with buy POE orbs Glassblower’s Baubles.