Hey!
I am trying to build an animation for an energy-shield. My idea: Particles like smoke or something else spread on the surface of a collider or object I set. How can I realize this?
The Unity Wiki has a shield shader that you may want to start from:
http://wiki.unity3d.com/index.php/Shield
If you want to use particles, I suggest looking into emitting them from a mesh. Take a look at the reference, specifically the Shape Module:
http://docs.unity3d.com/Documentation/Manual/ParticleSystemModules40.html