> Not much of a secret, but clicking the unsubscribe links in emails helps. Anything new I sign up to I'm pretty religious about it. Some new email I didn't ask for -> instant unsubscribe. Works way better than one might expect.

I usually do that and it works for a lot of things, but small hotels are one of the things that seems to slip through. And even when it works, I still resent having to do it at all, and would rather book via a big aggregator where I've already done the unsubscribe years ago.