I've recently got a new 4 wt. I matched it up with a Lansom Liquid reel and Orvis Hydros line that I already had.
I went out this morning and caught 6 bass (all about 3/4 lbs) and a couple of bluegill. I was getting ready to call it a day when I caught this bluegill.

It had eaten the fly pretty deep and my sling pack was about 30 yards back down the bank. The bluegill was about 10 feet from the bank so I went back and got the pack.
As I started back I noticed the fly line was moving. I then saw a heron (I think) scooting across the pond.
I reached the fly rod just as the bird hit the end of the line I had played out. I dropped the pack and reached for the rod a second to late. The rod scooted into the water and started skiing across the pond. I took a run and leaped out but missed it.
I stood up in the water and realized my phone wasn't in my shirt pocket. I was mucking around in about 3 feet of water looking for it and about ready to cry over loosing it and my fly rod/reel when I saw the bird go on to the bank on the other side and low and behold there was my fly rod up on the bank.
The pond I was fishing is in a housing addition and makes a kind of T. It was a really long walk by the bank and I wasn't going to lose over $300 of fishing equipment so since I was already soaked I swam across the pond (about 20 yards).
When I got near the other bank I managed to lose one of my shoes in the muck. I scrambled up on the bank and picked up the rod. By now the line was well into the backing. I started reeling and walking toward the bird. When I got about 50' from it I stopped and began pulling. The bird had swallowed the fish and wasn't going to give it up. That's when the 6 lb tippet broke.
I reeled in and started the walk back to drop off my rod at my truck and then on back to get my pack. My key fob had gotten soaked and wasn't working when I got back to my truck. I opened the door with my key and put the rod inside and headed back to get my pack.
On the way back I was really bummed out about losing my phone. It is my company phone and has an app for generating a key to log into my work VPN. It also has my company email and all my contacts. I planned on going back in to the water and trying to find it. I doubted that it would still work, but at least I wouldn't have to hassle with corporate security over a lost phone.
As I approached my pack I saw my phone! It had dropped out of my shirt when I bent over to try and grab my rod while it was still on the bank. I picked my stuff up and headed back to my truck.
Once back at my truck I found out that my key wouldn't start the truck. I got a message that said ignition failure. So I call my wife and have her bring me my spare key. She isn't real good with directions so I had her meet me at an intersection about a mile away.
Walking there barefoot I managed to get blood blisters on the bottom of my feet.
When my wife picked me up her first words were 'you stink'. We didn't talk a lot as she drove me to my truck.
I got in my truck, turned the key and it started right up. I drove home, took off my clothes in the garage, walked straight to the shower and spent a good while cleaning the muck off me.
So anyway, I didn't lose my phone, got my fly rod back, and just lost a fly, one pair of old water shoes, and have a key that isn't working. It could have turned out a lot worse and I got a good story out of it.