I love the idea for login systems that exponentially (or somewhat exponentially) prolong the waiting period. Eg 1 second, 2, 4, 8 and so on. There should be a r

I love the idea for login systems that exponentially (or somewhat exponentially) prolong the waiting period. Eg 1 second, 2, 4, 8 and so on. There should be a reasonable maximum of course, say 5 minutes. That would leave 300 attempts per day which renders brute force useless yet is low enough to not annoy users too much if you explain the motive.