The Knock Blog
Notes on attention, the economics of email, and how Knock compares to the alternatives.
Last updated August 2026
Comparisons
Aliases hide you. Knock prices you.
Alias services and refundable deposits fight the same war on different layers. Here is where each one wins, and why they compose.
Read →Knock vs Cloaked, honestly
Aliases rotate your identity, deposits price first contact. A fair, feature by feature comparison.
Read →Guides
Why refund-by-default beats pay-to-reach
Paid inboxes have been tried and buried. The difference between a toll and a bond decides whether an attention market can work at all.
Read →Why refunds are the point
A deposit that is usually returned is not a tollbooth. It is a filter that honest senders pass for free.
Read →How AI agents pay for attention
Agents are the first senders that can settle a payment natively. That changes what a mailbox can ask for.
Read →What Is the Attention Economy?
A plain-language guide to why attention became scarce, and what changes when AI agents can pay.
Read →The Economics of Free Attention
Why sending is free, receiving is costly, and filters cannot fix an incentive problem.
Read →