I like and use nostr:nprofile1qqs09jtvjlmyrxjn37zv70a89csegcz7rpyqjmnw29cveedhv7vagqqpz4mhxue69uhk2er9dchxummnw3ezumrpdejqz9rhwden5te0wfjkccte9ejxzmt4wvhxjmcpzpmhxue69uhkummnw3ezuamfdejs92xe5k because it uses Off-the-shelf components and the seed can exist in physical space loaded in via seed QR.