Commercial RSS F@#$ing Everywhere
Holy jeez. Whether there's actually any real interest or not on the subscriber side I don't know yet, but it seems that you can't throw a rock these days without hitting somebody who's offering purely commercial RSS feeds.
Yesterday Tuesday it was RealSimpleShopping (which, I might point out, I blogged before the Scobleizer got around to it), and today I came across Coupon Clock, which offers dozens of coupon/special offer feeds, grouped by topic. They don't (yet) appear to offer per-subscriber customized feeds, but since they've already got an email notification system set up I have to imagine that custom feeds aren't too far away.
Now to find out whether any of these guys are actually making money...