I've found a few useful things in the gutter over the years as well as rubbish. Things that probably bounced out of the tray of a tradey's ute. This week: large roll of 50mm bright yellow packing tape; and a couple of days later a 750mm solid rubber bungee strap in good nick. Previous finds include spanners and duct tape. The best find was a tool box, crushed by a truck. Unfortunately the half-dozen small tools were cheap stuff -- but I couldn't pass them up anyway.
I've never found anything as interesting as Sheldon Brown's eagle, Igor.
I only stop if I'm going at moderate speed and don't have to turn back. I don't stop for 'silver' coins unless there's a few of them. 'Bronze' coins are hard to spot but I have found $2 ones a couple of times.
Anyone else stop for 'treasures' and what have you found?