There's tons of tuts out there. You can model just about anything with the primatives, you just can't export them to other programs. I've made submarines, space ships, log cabins, etc in Bryce. You can also use a really fantastic free modeler called Metasequoia at http://www1.sphere.ne.jp/mizno/main_e.html I have a tut up at www.annsartgallery.com/eric.htm and might do more.