NXT will be hot in next three weeks. They announced an airdrop for all NXT holders. New coins IGNIS will be delivered to anyone who will get NXT on Dec 28
If you're interested, check their website for details https://www.jelurida.com/ico

The most interesting part is: "Half of the IGNIS coins will be reserved and distributed automatically to the NXT holders based on their account balances at the time of the Ardor Genesis Snapshot, at 1 NXT = 0.5 IGNIS ratio."

That's why NXT price was growing last week, I guess.