I have a somewhat modified mountain bike that is about a decade old.
I rode 30 miles today so far, going out for another 30-45 after I eat. I do touring on a mountain bike, which some people might consider to be dumb or inefficient, but it's actually a lot more comfortable than a hardtail bike. You'll never really realize just how uncomfortable hardtail bikes are until you ride a bike with rear suspension.
To me, ride comfort is more important than bike weight or speed. Admittedly, having a heavy frame, full suspension, and big, low PSI off-road tires means it will take more effort to go the same distance as with a lighter, more rigid bike, but I never feel any pain or soreness on this bike, even when going over lots of bumps or potholes for prolonged distances.
I started at about 60-80 miles a week but now I am doing about 200-300 or so. I want to keep up this pace, or maybe increase it.
I've been using the internet less and less and spending more time biking and I really love it. I feel so much more fulfilled and I really enjoy my free time nowadays. There are a lot of serene forested paths around where I live and it gives me this profound sense of enjoyment and contentedness.
One of these days I want to do a cross-country bike ride. I'm talking thousands of miles, going from the east coast to the west coast (I live in the USA). I've talked to people online who have done these kinds of trips and they say that they're amazing and sometimes even life-changing experiences. >>13
The trails I go on say that you need to announce when you are passing someone. It's for safety reasons. Most people shout, but I just use a bike bell instead. Announcing intent to pass is extremely important. People have made fun of my bell and say it's for kids, but safety is more important than people thinking I'm not stylish or whatever. When you're passing someone at like 10-20mph on a bike and they're walking freely, sometimes in the middle of the path, it is important to let them know they need to get the fuck out of the way, for both the safety of you and them. You never know when someone will dart out in front of you. If they don't know you're going to pass them, they won't make an effort to get out of the way.