Every Dreamhost hosting plan comes with one free domain registration. Some promo codes that you can use when you first sign up for a hosting account give you additional free domain registrations. People always ask whether these domain registrations are one-time things or whether they're for life.
The answer is that they're for the lifetime of your hosting account. That is, as long as you keep your hosting account, you'll get that free domain registration.
Also, the way it actually works is that Dreamhost will give you credits (one for most people, more of those that were lucky enough to have used a good promo code) every year for free domain registrations. You can use these credits to either register new domains or to renew your existing domains.
Use the [color=#CC0000]3DOM50[/color] promo code for 3 extra lifetime domains and $50 off
More Dreamhost coupons here!