I just downloaded and tried (via parallels) Google SketchUp. Wow! Does anyone else use this? Being a tinkerer by nature, this is possibly the most useful little app that I have ever used. It easily allows me to visualize and design things without worry! yeee! To give you an idea how easy it is, here is a design for a brick oven I am going to build this summer (it took me about 1 hour from installation to complete product):