Neobarok. The alpha for 2.0 was previewed a year ago. 2.0 is now being trailed on the site.
Totally free open source software, from one developer. Intuitive modelling and sculpting, with easy boolean and also paint.
It has good video reviews, and it looks quite promising for 2.0. There’s .OBJ export, but so far as I can tell there’s no in-software rendering of what you see to a big 3000px .PNG file. The best you can get there is switch to hi-res, go fullscreen, and take a PrintScreen screenshot.
The most vital first-step in using it is quite tricky, until you get the hang of it. To rotate:
1. First press down and HOLD the RIGHT mouse button.
2. Then do the same with LEFT mouse button, so that both buttons are held down.
3. Then move the mouse to rotate the view.
Do not just press both buttons simultaneously, as that won’t work.
It’s not insanely complicated like some software, although the basic camera and move controls are not initially very intuitive or standard. Let’s hope 2.0 has a camera widget like Poser.