Maybe this is common knowledge, but I just figured it out at the coffee shop this afternoon. If you point the iPhone to an RSS feed, then Safari will redirect it through reader.mac.com to generate an HTML layout for the iPhone.
I’ve got to admit, that’s going to make me tweak up my bookmark set now – at least so I can scan news on the iPhone a little better. Given a choice, I’d like to see what Brent would make for the iPhone as an RSS reader, but I expect that’ll have to wait until Apple opens the API/SDK a bit (i.e. at all).