So me and my friend have been farming for the new ether keys dropped from the new HoW patch today. We found the most effective way to find the chest. The boss to look for is Kalis-12, found at skywatch. He has about a 7.30 min respawn so it's quick. So far we've found: glimmer, various ammo synths, mats, rare engrams, legendary engrams, and there are also keys to the PoE chests. Give it a shot and collect those keys! Here is a descriptive guide to locations in all areas: http://www.reddit.com/r/DestinyTheGame/comments/36349w/guide_ether_chests_locations_found/ Edit: turns out you can only have a total of 35 keys. You can only have 5 in the vault total trying to put in another stack says it doesn't have enough space. So 5 on each character, 5 in the vault and 5 for each post master.