BitBetBot is ultra-simple but a cool usage of the "Zap" standard.

Try it out in your Nostr client of choice:

Yakihonne: https://yakihonne.com/profile/nprofile1qqszfeerq6v0md7pykuahrpsf472w20u3476tanr759f4rn2kauqjyqguvlfh

Primal: https://primal.net/p/nprofile1qqszfeerq6v0md7pykuahrpsf472w20u3476tanr759f4rn2kauqjyqguvlfh

Nostrudel:

.. or use your client of choice and search for: public key: npub1ynnjxp5clkmuzfdemwxrqntu5u5lerta5hmx8ag2n28x4dmcpygqpuu3gk name: BitBetBot