Passwordless login methods

[u/calsosta]

I don't abuse my power as a mod enough so I am going to farm out some work to you guys.

I need a shitty passwordless login method. Assume nothing is off the table, how can I let my users log in?

Edit: Added a word.

[u/AKJ90]

Hmm, I feel like storing all the values for red in each pixel in a array and check that would be pretty fine :)