The Pyramind is what I would recommend. Somewhat Ideal - in a sense that it captures, what I have managed (350 to 600 resources).
|CTO / VP / Operations Head||1|
|Senior Technical Managers/Architect/Quality Managers||7|
|Development Managers/Leads/Quality Leads||15|
|Misc (Web Projects)|
|Internet Marketing/SEO specialists||50|
|Technical Support/Night Sales||55|
|Org wide /Onsite/Client locations|