Put all of the postcodes in a paginated list that displays only 30 entries at a time (60 and 100 per page for premium users), only has next/previous navigation buttons, orders the entries by popularity, and goes back to the first page if you reload the website. Or an infinitely scrolling page that loads each page dynamically, but returns 429 Too Many Requests if the user scrolls too fast.
Map the tonal range of the human voice from 00000, the lowest-pitched, to 99999, the highest-pitched. Sing a note into your microphone that corresponds to your postal code.
EDIT: Make it a Base-36 range so as to allow letters A-Z when they are used in postal codes.
Put all of the postcodes in a paginated list that displays only 30 entries at a time (60 and 100 per page for premium users), only has next/previous navigation buttons, orders the entries by popularity, and goes back to the first page if you reload the website. Or an infinitely scrolling page that loads each page dynamically, but returns 429 Too Many Requests if the user scrolls too fast.
Map the tonal range of the human voice from 00000, the lowest-pitched, to 99999, the highest-pitched. Sing a note into your microphone that corresponds to your postal code.
EDIT: Make it a Base-36 range so as to allow letters A-Z when they are used in postal codes.
I reckon someone should try that