If you're really serious about having a beautiful basement, or if you want to get the most out of any remodeling project, you should pick up some interior design software. There are several options available in various price ranges, and many offer free downloadable demos so you can try before you buy.
Which design software to use?
When I originally began conceptualizing my basement, I used Punch's Landscape and Deck design program that I had purchased a few years before. It let me layout walls according to scale, and enabled me to quickly try out new floor plans, etc. Here's a look at an early plan:
An early draft of my basement design plan
After looking over the plan, I later decided to enclose the office (bottom left of the diagram) as a separate space, and to knock out the walls separating the work room. A new wall would enclose the entire 'furnace room' as one.
Better Homes & Gardens Interior Designer
When I finally got started on my basement remodeling project, I decided I needed something better. I purchased a copy of Better Homes & Gardens' Interior Designer. NOTE: The new version of this software has been renamed "Chief Architect Home Designer Interiors 10" It seemed easy to use, and was pretty cheap.
In addition to providing detailed blueprints of your interior designs, the software has an excellent 3-D rendering tool that allows you to visualize your basement designs. It even has a 3-D walk-through to give you a feel for what it will like once you are utilizing your new space.
After I installed the software, I downloaded some of the bonus items that added things such as additional furniture, and home theater products. This would help make my 3-D renderings more realistic. Here's a look at the software interface and some of the conceptual designs I came up with: