Make sure to turn on the volume so you can hear my beautiful voice. And download yours at https://github.com/fiatjaf/nak

What kind of uses cases does this enable?

You did it, cool

Could this also be useful for a recovery key to inform people to follow a new pubkey?

i love command line videos

Could this work like 2FA on Nostr?

An amazing video showing how you can sign notes cooperatively on nak using musig2: https://cdn.satellite.earth/ece156a65a2154fb5069bb3caf0cce2d9673caa71c3d06e2672b9bb2538d0c39.mp4