Cel shader

In the "Lighting preview window" i can check the "Cel-Shading" checkbox. It gives a very nice effect on my 2D sprites. Does anybody know of a shader to get the same effect in Unity?

I've played around with shaders, but I can't figure it out.

There will be a Sprite DLight update on Kickstarter soon, featuring a tutorial (made by backer Danilo Ganzella) on how to integrate packed sprites and Sprite DLight's normal maps with Unity. It will include a custom Sprite DLight shader that also supports Cel-Shading and it should be exactly what you are looking for.

Sounds perfect! Thank you for your response.

That'll be very helpful. Any chance it could support dynamic shadows also?

The tutorial has been published on Kickstarter and I have also added it to the engine integration list:

Unity 2D dynamic lighting tutorial with custom Sprite DLight shader by Danilo Ganzella

The custom shader doesn't support dynamic shadows but it supports cel-shading (which is also customizable).