HA! And you thought Wintersday items were done selling, didn't you? Actually, Sigils of Generosity are selling like hotcakes, with a nice little profit margin between buying and selling to boot!
At the time of this writing, I was flipping my stockpile of Sigils of Generosity for 3s 97c (originally purchased for 2s 50c). That's a profit of ~87 copper per sale. When you sell a few dozen every hour, it really does add up. Especially when you add a few more strategies to this one.
I just found it interesting that these sell so well, and I'm STILL selling candy corn trinkets from the mad king event (Halloween Holiday).
I think that with the next holiday special event, I will be buying up tons of the hottest seasonal items for the purpose of reselling them. Not necessarily the skins or mini's, but the gear that will show up on searches for even players who aren't looking for them.