This is something new to me.
Oh goodness! I think I figured out what dataware is talking about (in this thread). If you browse around Alexa's site, you'll notice colored boxes that represent the old style of Google Adwords boxes, labeled "sponsored links". When you click on it, it takes you to this page: http://www.adbrite.com/mb/commerce/purchase_form.php
Very, very unprofessional if you ask me!