Consider this my way of saying thanks for all the guides and exploits that have been posted here since GW2 launched.
Last night a guildy discovered a mystic forge recipe that produced ghastly or ghostly chests, identical to the previous mystic chest recipe (ecto+coin) except this time using cinnamon sticks. The chests gave some of the boosters you can get from the black lion chests, unidentified dyes, and some things that didn't do anything. It also gave a potion/tonic for the Lich form that Necro's get, including an everlasting version. My mate took a bunch of screenies, went to bed, and woke up this morning to find his account suspended for 3 days. He's put in a ticket, and when I tried the recipe it no longer worked.
There's a good chance ANet will change the recipe now, but on the off chance they don't, we've filled our inventories and guild bank with cinnamon. Since we can't buy any more, we've decided to give others a chance at getting it while it's still cheap. There's no doubt it's a risk - we could all be left with a mountain of useless cinnamon, but at least we can get half our money back by vendoring it. Decide for yourself whether it's worth taking a chance on.
The screenies are up at http://imgur.com/a/RJRh1, and to see that we've put our money where our mouth is, check out the supply of cinnamon at guildwarstrade (we've told some friends about it as well).