Every time I go to Venice or look through photos of the gondolas there, I see some new "method" used by the gondoliers there to protect their gondolas.
I laughed the first time I saw Vespa tires hung from the side. Long skinny black hoses draped along the side has been one of my favorites - it just looks so, I don't know..."festive/industrial" for want of a better term.
Tires have long been a favorite among mariners. Sure, you can go out and pay big money for the shiny, inflated, fancy-shmancy ones at the marine hardware store, but old tires are almost free. Plus, they use 'em on tug boats and any guy knows that tug boats are cool - right up there with fire trucks and race cars. Chances are most of the guys reading this are "grown-ups" now, but I'm sure you can identify with the whole tug boat thing.
I'm still not crazy about tires on a gondola though; it doesn't always look good. I'd rather see them mounted to the place where the gondola ties up or loads passengers.
All the same, here's a guy who cracks me up. He's obviously has had "issues" with the tail of his gondola bumping, rubbing or perhaps smacking up against something, and he's chosen to solve the problem in a cheap and effective way. I've decided to call it the "stick a donut on it" method.