I am quite impressed with Microsoft's WindowsClick image for larger version. 

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It is a simple 3D programme (although much more advanced than Xara 3D). It's main purpose is to create objects with the intention to print with 3D printers.
I'm not interested in printing but I love how you can quickly and easily take complex 2D designs from Xara and create standard 3D files in 3D Builder.
I especially like the Height map. Here is a mask I created. Most of the work was done on Xara and very little on 3D Builder.