Running history

As you know, for no good reason I dedicated this week to all-running posts. I guess this is to get it out of the way so I can get back to what I do best: complaining and talking about food. So how about a little running history?
I started running the summer between my sophomore and junior years of college. I had undergone surgery the prior year that had a rather long recovery period and left me partially thyroid-less. I felt like I needed to do something active to kick my metabolism back into gear. Anyone who's been hypothyroid knows how much it SUCKS. You feel so tired and lethargic all the time, and exercise leaves you breathless. No matter. I figured my oxygen capacity would increase over time, and it has. For the first couple of years of running, I just jogged. I would run on my street or around my campus' main block. Both routes were just 2 miles each. I only started increasing distance when I started running with my friend and eventual roommate Bj. He ran track in highschool and I had to keep up with him. Plus if I slowed down he would throw gravel at me. True story. A few months into running together, I ran my first race (The Crescent City Classic 10K) in about 48:30. Unfortunately after that I took a pretty long hiatus - I still ran, but not as often, not too far, and not very fast. That's because I started pharmacy school and basically had no time at all for running. Or eating, sleeping, and engaging in any activity labeled "fun". During my last year of school, which is all clinical rotations, I found I had enough time to run a little more. I wore my old shoes out and for the first time was "fitted" for running shoes.
The experts at the shoe store gave me extreme over-pronator shoes that weighed ten tons. I bought two pairs of these because I found a brand-new pair on ebay for super cheap. My knees basically died. I wore these shoes for over a year and during that time ran two half marathons, suffered knee pain that kept me up at night, and finally saw a sports medicine doctor for my knee. Of course I was labeled with runner's knee, but I think changing shoes helped more than any of the exercises I was supposed to do. I say that because while I did change shoes, I didn't stick to the PT very well. I suck at following directions. This was mid-marathon training, and I somehow managed to seriously injure my right knee around that time. This was a separate injury and in retrospect I think it was a ruptured bursa (something about the fluid filled joint as big as a grapefruit seems bursa-like to me). I ran the marathon this spring and it was wretched - I was slow, in pain, sick, and injured. Now here I am trying to train for another - please, injury free! - and work on speed a little. I've never tried to improve my speed because as soon as I switched from rare jogs to regular runs I started an injury cycle. A quick read of this story should suffice to prove that I'm not really a "runner"; I'm just someone who runs for exercise. I'm still working out when I should eat, what my pace should be, which shoes are best. And I'm obviously not very good at running, as you can tell by my race times and my injuries.
But you know what? I have about 1/4 of a thyroid and I don't take any medication for it at all (doctors are baffled). I live with clinically underactive thyroid and not only am I healthy, but I run regularly and I'm normal weight. I think being active has really helped me here. I'm actually walking around with not enough thyroid hormone (that is why I'm perpetually freezing cold and have a heart rate and blood pressure that are absurdly low) but I'm not overweight! GO RUNNING! I might just be running for exercise, but RUNNING, YOU ARE AWESOME EXERCISE!
So...Do you run, or what's your fav exercise? And if you do, why do YOU run? And how long have you been running? And are your knees the texture of sea sponges yet?