Or, you could take it to an Apple Store and they could find out who it belongs to and notify that person, the owner, that it's been found. The above method will wipe the data form the phone. But, I believe that it can only be activated on the original PC account that registered it with Apple in the first place. And if the owner has activated Find Me in Mobile Me, he could be tracking the phones location as we speak.
If you enter the passcode wrong multiple times (number depends on setup on phone) it should wipe the phone and be ready to connect to iTunes to be setup.
Or, you could take it to an Apple Store and they could find out who it belongs to and notify that person, the owner, that it's been found. The above method will wipe the data form the phone. But, I believe that it can only be activated on the original PC account that registered it with Apple in the first place. And if the owner has activated Find Me in Mobile Me, he could be tracking the phones location as we speak.
you found an iPhone 4? How do you found it?
Well, the best way is turn to Apple store...