I can't ride alone, of course: to effectively ride a bike requires a bicycle. I can recall with fondness each of the bikes I've had, from my first one-speed with red tires, to my current road bike, I've learned much on each one.
One of my favorites was my mission bike: a mass produced mountain bike with the "Liahona" brand (a reference from the Book of Mormon). It was a large mountain-bike frame with Shimano Deore components and a rigid tail and fork. When riding it as primary transportation, I put almost 100 miles-per-week on that bike, and learned lots of basic maintenance tasks as well. I eventually replaced a number of parts and after my mission, completed my first 2 or 3 century (100-mile) rides on it, much to the bewilderment of other riders. All told, I had almost 7000 miles on that bike by the time I upgraded to my current Trek. While not a great sum for many people, those miles represent the blood, sweat, and tears (as in "torn dress pants") from my mission and undergraduate university life.
A few days ago, though, I discovered Austin Yellow Bike, a local nonprofit which runs a community bike shop. People can come and learn how to repair their bikes, or they can spend time working to earn a newly refurbished bike. It felt like a perfect fit for my Liahona, so this evening I took it down and donated the bike. They seemed pretty excited to get it, and let me share the story and memories behind it. One of the volunteers mentioned that it was pretty neat to get a bike with a history, and I feel like it will be a good home for my old bike.
In the end, I'm glad I let go, but it was made much easier knowing that that somebody, somewhere, will be riding my bike (or parts of it) for many years more.