Several years ago, when I was much smaller, my parents bought me a mountain bike. If I recall correctly, it was a Pacific (kind of a generic brand), purchased for about $80 from Walmart. It wasn't exactly a great bike, but at the time I thought it was awesome. I spent a lot of time working on it, fixing flat tires (I managed to get way too many of them), and adjusting my brakes. A few days after I replaced the tubes and put a new seat on it, my Pacific bike was stolen. And then for several years, I didn't have a bike.
About six months ago, my dad bought me a cheap Huffy (another generic brand) at a garage sale. I fixed it and rode it around quite a bit. It was quite frankly, a piece of shit, and it broke quite often. After one of the bearing-cages in the crank assembly was crushed, my dad and I decided that it was time to try for another bike, and we eventually found a Trek 820 for sale on Craigslist for $20. At the time, my Dad and I had no idea what bike companies were good, and we didn't realize (nor did the seller) that the 820 was worth a whole lot more then $20.
The Trek 820 that I have is actually quite old, probably at least ten years old. It came with a 18 inch Cromoly frame, 21 speed, no suspension, mid-level Shimano components, 1.95 inch tires, and SRAM wrist shifters (although I've since replaced them with Shimano thumb shifters because the wrist shifters were pretty banged up). The current 820 has an aluminum frame and front suspension, and generally costs around two or three hundred dollars.
Since its a Cromoly frame, my 820 can't really compete with a light-weight aluminum-framed bike, but its still significantly lighter then my old steel Huffy. The lack of suspension is also a little disappointing, since at home I occassionally went on some extremely bumpy dirt-paths and a front-suspension fork could have been handy then. Nevertheless, its a good bike for getting around a not-so bike-friendly college campus. I can jump down small three-step mini-flights of stairs and jump onto curbs and sidewalks, while still being able to accelerate up to a decent speed that allows me keep up with most of the cars and motorcycles driving on campus (seriously, some of those motorized vehicles go really slow).
I have managed to eat dirt while riding my Trek on campus. It was quite a humiliating fall, and I was especially glad that no one saw me (it was fairly early in the morning and the school year had yet to start). I was moving at a decent speed through a patch of lightly-packed dirt, when I tried to make a turn. My back wheel slid out as I turned and the bike fell over with me on it. I slid for a nice distance, managing to do a great deal of damage to my left arm and my helmet in the process. But the accident was largely due to my stupidity and no fault of the Trek.
The old, Trek 820 is a good bike for getting around on easy unpaved bike trails and city streets. While its not a speed demon, I have been able to keep up with a trio of racing bicyclists on a paved bike trail for a good fifteen minutes while on my Trek (although I was drafting the whole time), so it can easily beat out a cheapy steel-framed Walmart bike or beach cruiser. So all in all, its a good bike, not particularly amazing in any way, but still a good bike.
And for good measure, here's a picture of my handlebars.