'Real' ( read as Xeon) workstations have been the unsupported crossbreeds between servers and clients.
For years servers have been managed using a "base management controller". In the OEM lexicon this includes technologies like Director, ILO, iDrac, ...
In clients( desktops and laptops) this need was filled by Intel based systems with vPro which have AMT - Active Management Technology.
In either of the above, out of band management allows remote device management at the hardware level. This is fundamentally different than what you can do with a software agent. OOB management allows you to remotely do low level functions - lilke power on, power off, reboot, format, partition, bios, etc... all of which are not exposed through an agent that runs on top of the operating system.
OOB management is a critical tool for server management, and with vPro is becoming a critical tool for client management as well.
Up 'til "now" OOB has been missing on workstations.
With the E3 family and C206 chip set Intel first introduces AMT into the workstation family. This will continue into the two socket space when the 'Sandy Bridge' products launch this fall! This is seriously exciting. Customers can use the same tools to manage fleets of Xeon based workstations as they do to manage their vPro laptops and desktops!
OOB management can dramatically reduce support cost and travel time, keeping support staff efficient, and get your workers back to work faster.