I found $400 cash in a small change purse on the street one night, coming home from work late.
The only other thing inside was a seniors bus ticket.
I turned it in to the police.
I took heaps from my friends for being a chump, even the police officer who responded said he wasn’t sure what he’d do if it was him.
This was on one of the Slider episodes where the media and cops baited people.
I also responded based on memories of the Reader’s Digest test. I remembered it being somewhere in the vicinity of 2/3 returned, so picked one of the answer choices on that cusp. I’m not sure what I would have guessed, absent that.
I once left my wallet in a taxi, it was returned within a few hours even though the driver had to do some research to find me.
I also had a shoulder bag stolen from the back of my chair in a mall food court once. I never saw the bag ( which was leather and really nice - or my wallet ( which was relatively cash poor ) again but within 3 hours someone had dropped off an envelope containing my ID’s, credit cards, one of my business cards and an airline ticket ( it was actually a set of old flight documents in the paper holder, but the thought still counts) at the security desk of a nearby office building. They called me and I got all my important stuff back ASAP. I was still peeved at losing the bag but I was glad I was victimized by a considerate criminal.
I tend to think most people are honest. I am chronically losing things, and while I usually find them in my home or car, I lose them in other places from time to time.
I’ve lost my wallet on more occasions than I can remember. I’ve always gotten it back except once, and it’s just as likely I dropped it outside someplace or that the contents were scattered. Nobody tried the cards or anything.
I’ve dropped cell phones, too, and always gotten them back. Usually I have to call around to the places that I’ve been and one of them will have it – if they don’t, I generally intensify my home/car search and it turns up in someplace weird. On one occasion, though, the movie theatre attendants who found it changed the wallpaper on the phone to a slideshow of some rather risque images from my sister’s bachelorette party. They seemed really disappointed when I showed up and revealed I wasn’t one of the young ladies in the picture. 
I just tend to lose stuff. The worst places for me have been hotels – if I forget an item in the room, it’s somehow gone forever (at upscale places and ratty old ones, it’s all the same thing). Usually the item I lose is bedding-related (I like to travel with extra pillows and blankets), so you know the cleaning staff found it when they made the bed*. That’s the one area where things seem to drop into a black hole… losing items at other areas of business always seems to work out OK.
*Tipping seems to have no effect on this phenomenon so I wonder if it’s just that the staff is so stretched that they just throw things away rather than turning them in, or the front desks/management takes stuff, or they’re just too disorganized, or what. I have called within an hour of checking out knowing I left something behind in the bed, they say they checked the room and nobody else has checked in, but it’s not there. Even large items (e.g. body pillows)!
I’ve never lost my wallet, but three times I have found one. My actions were based primarily on my age at the time:
12 years old - $80. It was more money than I’d ever seen in my life. I pocketed the cash and trashed the wallet.
18 years old - I don’t remember how much money was there, if any. The girl it belonged to looked cute in her DL photo. Tracked her down and returned the wallet. Nothing ever came of it.
30 years old - Again, I don’t remember how much cash was there. I tracked the person down and returned the wallet, because it was the right thing to do. I got $20 for my efforts; I told the guy it wasn’t necessary - he came to my place of employment to pick it up, after all. But he insisted.
Some will keep it, for various reasons. I split those into two general groups: those who are in desperate need, and view it as a miracle and a help that they found it, and those who don’t think the loss would hurt the imaginary people and so keep it. Ok, add the third group that don’t care whether the loss would hurt, but as it’s a bonus to themselves, that’s what counts.
The people who would return it are also split into groups <in my mind>: those who might really need it, but it isn’t ‘theirs’, and they haven’t ‘earned’ it, and so return it. There are those who don’t need it anyway, and would return it because it would cost them nothing to do so. I think the largest percentage are on the edge, but would return it because it’s the right thing to do coupled with the fact that it wouldn’t be THAT big a save for them to keep it.
I would return it, unless I was desperate. I would certainly consider it a boon to have found it if I WAS desperate enough to begin calling in godly favors. At that point, I’d return it at a later date, when I was in a position to ‘pay back’ the unwitting loan.
On the few occasions I’ve found money and/or wallets, I try and return them. I think the most honest I’ve ever been was seeing a stereotypically rich guy step out his huge Mercedes and into a bank. He dropped a clip full of cash that was probably half an inch thick. I picked up the cash, stopped him and returned it. He walked off without saying a word. Twenty years later, I’m still waiting for the Karmic refund.
Hell, I once found a $20 on the floor at Bob Evans and handed it in. If it aint my dinero, t’aint my dinero.
I’d keep the money, because the people are all imaginary anyway.
I once found a woman’s handbag in a phone box. It had, IIRC, about £30 in it, plus some other odds and ends. It so happened that I knew there was a police station just a couple of blocks away, so I took it there. The lost property clerk (I do not think he was an actual cop) looked at me quite suspiciously as if he thought I had stolen it. He slowly inventoried all the contents in front of me, and I had to give my name and address and (IIRC) sign the inventory. A couple of weeks later I received a letter from the owner, thanking me, and inclosing about £3 or 4 as a reward. Oddly, though, this actually made me feel rather bad. I remember thinking that if I had had the gumption I could have had £30 rather than just a lousy £3 (although I had had no thought whatsoever, previously, of getting anything).
Still, I think I would almost certainly do the same again (and not expect any reward). Also, the greater the sum the more likely I would be to return it.
OTOH I did once find what I thought might be a diamond ring (it turned out not to be) in a parking lot. I saw a truck run over it, and it got squashed and the stone came out of the setting. That I kept, but, of course, I had no clue as to who it might have belonged to.
I’ve returned a wallet with money in it before and I’d do it again. I guessed that about 30% of people would keep it.
In my youth I would’ve done everything possible to find the owner, but now in my “old-th” and over the 45 years on Earth I’ve lived, I’ve lost major amounts of money and no one has ever returned it or even tried.
I know you don’t do kindness for return but it’s just the way I feel now.
Or take it a step uglier, lay out bait wallets with counterfeit money in them. Might make for a hell of an object lesson in morality for those who chose to keep the cash.