Simulation based proofs: Simple examples I am aware that,(in theory) in order to proof that a scheme is secure using simulation based proof we replace an adversary in real world with a simulator in ideal world. Then we try to show that their view are (computationally) indistinguishable (if the scheme is secure).  

What I need is some simple examples (in zero knowledge or secure multi party computation) that use this idea to proof. So how the simulator is constructed, why sometime we use an adversary to interact with the simulator are not clear to me. 
Any reference to a paper or explanations would be much appreciated.
I have written a tutorial on how to write simulation-based proofs. I think that it should be helpful.