I get a lot of email that I’m interested in reading, but which I don’t want cluttering up my inbox. In the past, I tried creating a mail rule that would immediately archive mails (keeping their status unread) with a sender address matching those within a long list contained in the rule. That got unwieldy after a while, since Mail.app’s rules definition interface wasn’t really meant for managing very long lists of conditions, and so I abandoned the rule.
Recently, though, I had a better idea — adding all theses senders to a “ReadLater” group in Contacts.app, and then having my Mail.app rule contain a single condition—i.e. checking whether the sender is a member of that group. Works great, and easier to identify just those mails in my Smart Folder for later reading.