Ross recently stated on a different thread that he had created a plug-in for SketchUp to give a pencil type effect. This reminded me of an Android/OS app called Prisma that can also add pleasing effects. I know Gary P uses this too.
Here is an example of the type of effects that can be achieved. It's not just a simple filter, the filter effect can be varied. The image can be saved & further effects added etc.
LINK
Apologies re the crap audio
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