If it had a name, or if it didn't, I'd hand it in to the police.
This is one of those grand dilemmas - if you find a tenner and nobody's about, do you pocket it? If you see the tenner fall out of someone's pocket and they have no idea, do you still pick it up, or give it back? If you found £100 with no name on it....?
I found a wallet stacked with money. Inside there was a buisness card. I rang the number and the guy couldn't believe his luck. I made him tell me what else was in the wallet, as at the time I thought we all carry buisness cards, maybe it's not his. I'd like to say he rewarded me with a new car. (he didn't) It was reward enough seeing the look of relief on his face.
I found a cat when I was looking for Rover - fortunately, I managed to trace his owner the next day and reunite them, otherwise he would have been labelled as a stray....
You have to be carefull as I'v heard of storys when some one was honest and found a wallet with money in it,took it back to the owner and insted of being thanked for it,been acused of stealing it then taking money out of it when that wasn't the case what so ever. Some people will find them,take some out then dump it again leaving it to be found a seccond time then being accuse of theft because some of the contence has already gone. Your best off either going to the police with it or leaving it alone if your not the one to keep it for yourself. You can put yourself at danger trying to find a stranger and showing them you have their belongings when you don't know who they are or what state of mind they are in.