I got another good one that happened when I wasn't fly fishing, but I was after some channel cats with minnows.
I had an old dip net that I persuaded my uncle into buying for me when I was 8. A few years later, I was using it to net some minnows when the stringer I was using as a rope came off. I was pretty upset, but I decided to keep on fishing. A few hours later, I had a nice hit and set the hook. I had a decent fish on the end and then all of a sudden, I got snagged. Eventually, the snag started moving slowly towards me. When I landed it, it turns out that a hefty channel catfish tangled himself and my line on my net! So, I got a nice fish and my net back!