Acronis uses Drupal for their Knowledge Base

It's always cool to see large organizations implement Drupal. Acronis (software vendor specializing in backup and disk utility apps) has leveraged the power of Drupal's core node and taxonomy systems, as well as powerful modules like webform, to provide their community with an intuitive, simple, and well-mapped system -- at a fraction of what it would cost them to have built it from scratch.

Check it out at http://kb.acronis.com/