I think everyone knows this, but considering the interest in panoramas for the fake hdri thing, its real easy to make panorama scenes in Bryce. Double click the render button and select "cinemascope". That gets you a wide format render space. Just to the right of all the render buttons is a down arrow. Click that and select 360 degree panoramic projection. This way you can make your own panoramas and not need to find them on the web.