Bypass Surgery for Clogged Inboxes is the title of an article by Rafe Needleman:
Relevant Reach sells a product that connects software publishers with users through a channel embedded in the application itself. It’s essentially a small e-mail client to which the publisher can send updates, offers, and so on. A subtle (or garish) indicator can alert users to new e-mail, or the message window can be accessed from a help menu — it depends on how the publisher wants to use the application.
It also has the interesting characteristic of being anonymous — users can send e-mail to the publisher (with tech-support questions, for example), and the publisher can reply. The application shields customers’ identities and addresses, so users won’t get any junk mail in with their regular e-mail; customers can also skip the annoying demographic survey that many applications require for registration. All the publisher knows is the serial number of the installation a reply is going to.