I've been playing around with this 3D Home Architect, and I'm somewhat impressed.

It has a few bugs (like putting 4-ways switches at each switch location when three switches are used for the same light) but overall it works well.

Here's a small floorplan of my existing shanty for a demo:

[Linked Image from users.sgi.net]

3D Home Architect Deluxe

I picked up the 3.0 version for $9.99 at Wal-mart, it's very user-friendly and will make my bids more professional looking.

Give it a try if you're looking for a cheap alternative to CAD.

-Virgil
Residential/Commercial Inspector
5 Star Inspections
Member IAEI