Ever hear the one about the all-night locksmith? I have. Twice. It gets old fast. Anyway this is how it goes: This poor single mother, Doris, decides to take her four kids into the big city to see Disney on Ice. Everyone is very excited and has a great time. Donald is great, Mickey is great, everything is just great. So they get back to the car, and the kids are still so wound up from all the excitement of all that Disney on Ice that they start getting rambunctious. They grab the car keys from poor Doris, start throwing them around, and wouldn't you know it? They go right down a storm drain. This is the worst thing that could happen to poor Doris. She has no cash on her, no one to call, and no credit card. She manages to get in touch with an all-night locksmith, but it's going to cost her to get him out there and get the car open. What's a single mother of four to do?

The punchline is: I gave her fifty bucks. Yeah, I didn't think it was that funny, either.

I got scammed, and I knew it. Or I suspected it at least. I walked away convincing myself that Doris was running back to a car-full of happy children and not to her dealer. The real humor in this story is that she approaches me a second time, three months later, in the same part of town, with the same story. Remember when you found out Santa Claus wasn't real, even though you already sort of figured it out? That's what it felt like.

Want to hear another one? This brave single dad Adrian is driving in the big city with his little girl Veronica. She has to go to the doctor or something. They're driving right along when they run over some broken glass and bam! flight tire. And of course there's no spare. He must have used it helping out some poor family in a jam and forgot to replace it. Or maybe he sold it to buy his daughter braces, I don't know. Like I said, they're stuck by the side of the road with no credit card and no cell phone and nobody who cares for them in the world. He can't possibly afford a tow, so the brave single dad (did I mention he's a single father? Isn't that touching?) leaves his daughter waiting by the car and heads out looking for help.

Go ahead, guess who they find.

"You can tell by my clothes that I'm not a beggar." He says this to me. For real. As if that's how people who AREN'T beggars, who actually need help, talk to people who are offering that help. But I keep talking to him anyway. Mainly because of his daughter, or more accurately, the possibility of his daughter. The one he left all alone, in the big city, waiting by the car. And where is this mystery car? "I don't know the city so well, so I can't explain where I left it. But don't worry, I know how to get back to it." I wasn't totally convinced by him, despite his non-beggar clothing, so he only got twenty bucks. Enough to cover the tire patch kit from the hardware store, which increased in price incrementally from the time he first mentioned it (five dollars) until we made it to the ATM. Yes, I took a stranger, someone I suspected to be a con artist, to the ATM with me. Yes, I am incredibly naive, thanks for asking. But at least I never had to see him again. Can you guess where this is going?

One month later I run into him again. Same part of town, same story. "I'm from out of town, and I've got a flat tire. I'm wondering if you could help me out..." I call him on it. I tell him he used the same story on me a month ago. He starts laughing. "I'm surprised you didn't punch me!" Then he pats me on the arm and walks away. Ba dum bum. Now that's comedy.

These are just the repeat offenders. The big ones. Not included are the small-time con artists: the guys with clipboards, the religious zealots, the out-of-towners without kids, and the standard beggars. They've all gotten money out of me at some point, just never that much. And of course, I've never recognized them a second time.

It's not even that I believe them all the time. It's more that I'm overwhelmed by a sense of compassion for them. My softheartedness wins out and I hope for the best. Is this a bad way to be? Doris didn't think so. In fact, as she was taking my money she remarked, "Your mama raised you right. She must be very proud." Yeah, I can hear her now: "This is my son, he gets suckered by con artists all the time." Stop, Mom, you're making me blush.

Sometimes it's easier to part with a few dollars and feel like a sap than it is to walk away and feel that maybe, just maybe, a kid somewhere is crying because of you and your stingy pockets.

And both these stories got me in spite of myself. I was kicking myself as I was handing the money over, but I did it anyway. Why? A quick analysis of each situation reveals more than a few similarities, and a few key details that made them too good to resist.

Both involve single parents (how touching) bringing their children into the city and meeting with car trouble. Neither can get help from the usual avenues (i.e. tow trucks and, ahem, all-night locksmiths) and must turn to strangers for help. They both also displayed a willingness, if not an urgency, to repay the money the next day. The each offered to leave me their address so that I could find them again. The woman even offered to leave her license as collateral (would-be scammers take note: it's the little details that get you the big money). And they were both very polite. But it's the kids that get me. Those poor kids sitting alone by the car. I don't know if it's true that babies can sell anything, but they sure can sell a half-baked story with gaping holes and inconsistencies.

"He wanted your money. There was no daughter and no car." That's what my friend Beth had to say about good old Adrian when I told her about my first encounter with him. "What parent doesn't have a credit card?" She had a point. And to date, she's never been successfully scammed. Like most of my friends, she gives only out of guilt instead of gullibility.

But like I said, it's not so much that I'm gullible than it is that my logic gets clouded by my own sense of right-doing, a sense that I seem to emanate. Waiting on crowded street corners I've had beggars and con artists make a straight line to me, not even pausing to consider other potential targets. Somehow they know that I'll stop to listen to them, something I do through a combination of politeness, curiosity, and compassion. But is that something that can really be broadcast? Maybe not, but there are other cues that make me worth the risk. I'm usually walking alone, I'm not particularly threatening, and I'm too wrapped up in my own little world to see them coming. Though the best explanation I've heard comes from Beth: "It's because you look so sweet and approachable. You don't look like you'd yell at someone."

But there's hope for me yet. A few months ago I was walking up Newbury Street on my way to meet my friend John, and I got stopped by this man with a stack of Spare Change newspapers in his hand. He starts going into his routine and I say, Yeah, I'll take one, and give him a dollar. He starts pressuring me for more, and I say, Wait a minute, what about my newspaper? "These?" he says, "Oh, I'm not selling these." So I tell him I want my dollar back. I thought I was buying an issue. We go back and forth for a little bit and he finally hands over a paper, and I accept it with no real intention of even looking at it. A few minutes later I'm walking back down the street with John and this time the Newspaper Man stops him instead. He gets a few lines into his pitch when he stops and sees me. "Oh, you're with him." And he walks away. Hooray, moral victory!

And that seems to be representative of my role, to alert others. I've had more than a few people tell me now that when they are approached by an unusual character with a shady story they think of me and promptly walk away. One friend was prepared for his own run-in with the Newspaper Man. Another was able to turn away an organizer for a "special dinner for the homeless" one week after I had met up with him. Still another walked away from a would-be psychic who was attracted by her aura (I can't take credit for this one, but she did say she thought of me). But my favorite was from a friend of a friend, who ran into a woman in Atlanta who claimed to have lost her keys down a drain and needed to contact an all-night locksmith. He told her, "I heard about you in Boston," and turned away and left.

And it feels good, knowing that I'm making a difference in my own, backwards way; helping others to avoid the same pitfalls I fall into. Almost worth the fifty bucks I lost.