I for one will be keeping an eye on this thread as I find the subject outstanding.
If I may propose people give serious answers on
1. the most difficult single situation, as in "my car broke down in the middle of an unlit mountain road at 2am in a particularly heavy winter blizzard and i thought i was gonna die" type
2. difficult life situations, i.e. "was homeless for 9 months"
I'll bite with a response like #1 to make up for my sarcastic earlier reply.
One of the most difficult situations (at the time) I have ever been in: One year during college, the lock cylinder on my VW Jetta froze. I could not turn the key in the cylinder to start the car, effectively making my car inoperable. The electronic security system would not allow me to bump-start it or turn the wheel. To make matters worse, I was working at an internship in the town of my college through winter break, and this occurred 3 days before Christmas. I needed the car for a 4.5hr drive to get home to see my family. I was also in the far north, and the snow was comin'
The stress began to build.
Trying to muscle the steering wheel and cylinder, the key soon broke off, flush with the edge so I couldn't pull it out. At this point I was getting desperate and frustrated.
I wildly searched the internet, looking for a solution. The only thing I found was towing it to a shop. This was obviously out of the picture due to Christmas looming. As my education was in electrical engineering, I began to think of how the cylinder interacted with the cars ECU to tell it to start. A day went by. Now it was the day before I had to drive home. Getting home from work that night I got back to business on the car, my mind burning, determined I would make it home in my German sleigh.
I eventually pried at the other side of the lock cylinder, which was attached to a small connector with two or three wires. This cap that was attached had electrical connections on the inside, about three of them in different ring formations. I deduced that the turning of the key (and cylinder) connected different parts of these rings to each other, which corresponded to different modes and eventually ignition. I took a small piece of wire, and began poking at different parts of these pads. At first, the lights of the car came on, and if I held it just right, stayed on.
Then I had my moment. Touching one end of the wire to the inner circle, and then to the outer circle, the car began to turn over and come to life! But I had another problem, it didn't stay on once I removed the wire.
I took the cylinder-end inside, and looked for what I had in the house. I ended up soldering wires to the connections on the cap, and using a light switch to start my car. It felt and looked like a hotwire.
So I began to drive home the next afternoon, elated that this tribulation was behind me. As I was going down the highway, my car died. I coasted it to the side of the road. A policeman came up to my passenger side window, where my girlfriend of the time was sitting. He took one look in with his flashlight and looking at a tangle of wires and a light switch under the steering column, in my lap, he said "are you alright?". My girlfriend was the type to pipe up in this situation and she uttered "He's an electrical engineer!". The cop responded with "Oh come on man, you should be able to figure it out!"
I twisted the wires around, and regaining a good connection, started the car back up. The police officer left, and I drove the rest of the way home.
So ended one of the most difficult moments of my life (at the time).
I say at the time because now I look back and figure I could have just rented a car. Undeveloped, broke, college mind me didn't factor that in.
Not the most serious of circumstances, but to a young man with untested mettle it was a good lesson in self reliance.