Never lost a chair, but I did lose some beer in the Dane near Middlewich, years ago on a really hot summer's day. My dad brought a four pack for us (I was about 14 at the time so it was a bit of a treat) and we put it in the water in a landing net to keep it cool. After wandering further upstream, trying out a few different swims, we returned very ready for a nice cool beer, only to discover that the net had tipped over and allowed the cans to float off downstream. I went running down the bank, hoping to find them, which I eventually did - they were being drunk by a bunch of teenagers who had been swimming in the river! So if any of those lads are reading this, you're welcome!