In Nitrous viewports, you can choose various visual styles, including "non-realistic" styles that resemble artistic media such as colored ink and acrylic.
Note: You can render to these styles using the Quicksilver Hardware Renderer. For details, see Visual Style & Appearance Rollout (Quicksilver Renderer).
The default style, Realistic, is comparable to the result from a hardware rendering. Other styles have effects that mimic artwork created by hand with (for the most part) more traditional media. These illustrations show the kinds of effects you can achieve.
Realistic (the default style)
Ink
Color Ink
Acrylic
Tech
Graphite
Color Pencil
Pastel