I live in Chicago and work downtown, so I get hit up by bums multiple times a day. My best story:
One evening, I was at a bowling alley and stepped outside to smoke a cigarette. While outside, a young (early-20s) white man with decent clothes and a baseball cap approached me. He told me has was from Valpo, IN and came into town via train for the weekend to visit friends and was getting ready to leave to go back home. He asked me for directions to the train station and pulled a piece of paper out of his pocket which described which station he was departing from, which train, etc. He's just asking for directions, and he has paper with his train info on it...seems legit, right? I told him how to get there and he thanked me. Just as he was about to walk off, he turned and began his spiel. He told me he was supposed to leave the night before but he was mugged prior to getting to the train station. Three black guys jumped him and beat him into unconsciousness and then stole his wallet which contained all of his money and train tickets. The train tickets were $40, and if I could lend him the $40 he promised to pay me back by wiring me the money as soon as he got back to home. He pleaded that he was just a normal guy but in a bad situation and assured I would get the money back. I told him I didn't have any money and he just walked away. I figured it was a bullshit story but whatever...back inside to bowl.
About 6 months later, I was at work one day and left to go grab some lunch. (Keep in mind, my work is about a mile or so away from the bowling alley that I was at that evening.) As I was walking to grab a bite, a young man approached me, wearing a ball cap and asking me if I had just a second. He looked familiar, but I couldn't place it. Just as he was about to ask me something, he pulled a piece of paper out of his pocket with some handwriting on it. I immediately realized it was the same guy from before and this was a scam. As he asked me for directions to the train station, I cut him off and told him he wasn't getting a fucking penny. He stopped, and looked at me as if "how dare you." He then said, "Excuse me, sir, but I wasn't asking for money. I'm only asking for directions to the train station as I'm from out of town. How RUDE of you!" I told him I knew he was full of shit because he tried pulling the same scam on me about 6 months ago. He quickly took off down the street.
I went about my business and about 30 minutes later I was walking back to work when I come across the guy AGAIN talking to an older woman. He had that piece of paper with his train info in his hand, showing it to the lady, and giving her that BS story, as she was digging into her purse to give him money - I saw her pull out at least a $20. I didn't do anything but continue on my way back to the office because I figured that lady was a dumbass for falling for his scam. However, I regret thinking that. She was just trying to do the right thing and the scammer was taking advantage of her kindness. I probably should've said something to the lady. Oh well, I guess we all have to learn a lesson the hard way sometimes.
Aside from the above instance, I get hit up all of the time. Chicago must be the bum capital of America. Usually, I just ignore bums. Sometimes that makes them mad and they start running their mouths. Then I tell them to fuck off, get a job, etc. Threaten to whoop their ass and they shut up and move on. There have been a few times I have told the bum I don't have any money and received a look back like I'm an asshole for not giving them money - like I owe it to them. I've even been called a liar (that I did in fact have money on me) a few times.
Occasionally, I feel generous and hand out a buck or two but that is only to the ones who are playing an instrument or actually doing something. Almost every time I see a sign that says "Need money for beer" or something honest and comparable, I will throw down a donation.