I've said over the past month that the "killer feature" of Nostr will be **Lightning**. The fact that Lightning is so tightly integrated on various aspects of clients and soon relays, it makes using Lightning so effortless and frictionless. Beyond that, people tip each other and post invoices and show that it's fun! I've had a couple dozen people DM me and tell me that they had never used Lightning before. Nostr changed all of that for them. They downloaded their first wallet. They setup their first Lightning node. They opened their first Lightning channels. Nostr will help fuel Lightning and Bitcoin's adoption.