I don't find these long render times a problem... although 10 days is a little excessive! There's no problem with continuing work in other apps while Bryce is crunching and... I'm not too sure about this, but is Bryce the only app which allows you to save a render somewhere in the middle and continue rendering at another time? This feature is EXTREMELY useful... I render overnight and through the day and work on new stuff in the evenings. But of course I'm ONLY a hobbyist! These speed-freak pros must think we're cRaZy!