What do you use to map your network onto a great diagram?

Some folks use automated tools to map networks, like Nortel’s Enterprise Switch Manager, or HP OpenView’s Network Node Manager. Others use a manual solution and track links through documentation and then draw the network with Visio.

What application do you use to map your network, and how well do you like it?

Does your solution cover all vendor brands, or if not, which ones does it get along with, and which do you know it doesn’t like?