For those interested in circuit design, check out LT Spice from Linear Technologies (http://bit.ly/HAEw9). While mainly designed for use with their products, you can use products from any company if you have the spice models. It was designed mainly for their switching products, but I have used it to model circuits other than those successfully. And best of all, it's free! http://egmgem.com http://gitonga.imagekind.com