I'm just coming ou of a major block myself - so I know just how frustrating it can be! What I do when inspiration won't come is to concentrate on learning more about the software - fnding tutorials on aspects of it that confuse me (like lighting!) and working through them. That way, I'm investing the creative downtime in improving my techniques, so that when I'm back into creating, it's easier to get the effect I'm after. Alternatively, as someone else suggested above, try working with a different bit of software for a while - I alternate between bouts of Bryce and Poser. If all else fails, just put on some loud music, and illustrate the emotions it invokes! And whatever you do, remember that this is supposed to be enjoyable!