I have so many but the one I always look back proudly on was non-technical and fairly devious. I was a disaffected middle-schooler. I had lost my science book w

I have so many but the one I always look back proudly on was non-technical and fairly devious. I was a disaffected middle-schooler. I had lost my science book which I would have to pay for if I didn't find it. I had, however, "procured" someone else's science book. The problem was that all the books had been numbered on the edge by the teacher who kept a list of which student had been issued which book. I wanted to somehow make the number of this book match the number of the book I had lost but they looked nothing like each other. So ... I took a marker and crossed out the number on the book. Then I wrote the _same_ number right next to it. Then I took it to the teacher. I said "Hey someone stole my book and tried to pass it off as theirs!" The teacher took one look at it, said something like "what an idiot" and then proceeded to update the list with my name for that book instead of the original owner's. I don't know what happened to the other kid - it never came back to me. I felt bad later but believe me it was a deeply satisfying minor victory for me at a time when not much was going my way.