Years ago when we were running jd 55 combines we had rice tires on the front and mounted them backwards. This way you never got so far into a mud hole that you couldnt back out. Never tried it on our later combines as we had 4 wheel drive and the balance was different, as well as being heavier.
The reason we have our drive tyre's on backward's is because when we walk them on the sealed road's they have a better life span, and they also walk out of a bog better, like Eric mentioned in his post...