I bought my Rivendell in 2001. It's officially 12 years old now and going strong. The beauty of the bike design is that it can do so many things. In less than 20 minutes, I transformed it from an fendered & racked utility bike, to a knobbie-tired trail runner.
My bike isn't unique in this ability, but there are a LOT of bikes that are sold that can't do it. Whether their tire clearances limit them to 28mm, or full suspension bruisers, the are purpose built. It's hard to find bikes that can get close to both. A Surly Crosscheck and Black Mountain Cycles MonsterCross are great examples, but they are pretty niche market machines.
So take a peek and see what a well-designed bike can do for you: http://www.flickr.com/photos/cyclotourist/sets/72157602592825848/with/8587829042/