Yes, you read that right: I love taking pictures in and around parking garages. I attribute this partly to being raised in Los Angeles, where garages in general are much like a second home (and where, for the unfortunate, they actually are home).
Parking garage, Beverly Center, West Lost Angeles (shot on Kodak Tri-X film)
It may also have something to do with the industrial arts (a.k.a. drafting) class I took in junior high school. I had to create drawings of buildings and mechanisms from various perspectives using nothing but a pencil, T-square, triangle, and compass. A year of that will give you a deep appreciation for lines, angles, curves, mass, and shape--either that, or you'll hate it and turn to landscape photography. You can see what path I took.
Empty parking garage, Cheltenham, PA (with understated HDR effect)
The trick to getting good photos in a parking garage is knowing how to deal with extreme contrast. The light inside the garage can be quite dim, while the light outside can be five stops brighter. You could go the HDR route to open up the shadows and reduce the brightness range to something printable or you can do as I do, which is to expose for the highlights and let the shadows go black. I do this as much to hide a garage full of boring suburban SUVs, sedans, and minivans as for its graphic effect.
Parking lot, Beverly Hills, CA
Another thing that helps is a tripod. Given that I'm in or near a garage, I'm generally near my car. My car has a trunk ("boot" to you Brits) that in turn contains my tripod. The tripod allows me small apertures for more depth-of-field and low ISOs for maximum image quality. A tripod also makes it easier to make sure that everything lines up exactly the way I want it, shot after shot. Just remember to watch out for passing cars. Not only could one of them crush you under its wheels, what's worse is that it could shake the tripod and ruin the shot.

I agree with you on that front... I discovered it quite by accident though, as part of doing a 365 Project (just get to snap pictures in random places).
What I love is the concrete, and the texture that comes up as part of it.
Here is a quick sample of some of mine.
http://www.flickr.com/search/?w=58909744%40N04&q=carpark&m=text
Posted by: Chromatic Dramatic | November 08, 2012 at 10:47 PM
Ever seen the parking garage in New York at the end of East 23rd Street and the East River? It's the automotive equivalent of Frank Lloyd Wright's Guggenheim.
Posted by: Ben | November 09, 2012 at 09:08 AM
There are few things in life finer than a good parking garage.
Posted by: Stephen Connor | November 09, 2012 at 09:15 AM
Striking photos! That first one is a real stunner.
Posted by: Nikhil Ramkarran | November 09, 2012 at 10:19 AM
Parking garages also provide a great place to get elevation for shooting pictures of other things, a fact which I know you've used to excellent effect in the past.
Posted by: Nicholas Condon | November 09, 2012 at 12:13 PM
I find the concept of exposing for the highlights is my preference for city environments too. Big cities like Chicago have lots of contrast during the day. Letting the shadows go black brings out the graphic qualities of all that architecture. I like it in both B&W and color images.
Great images Gordon!
Posted by: Mark Kinsman | November 09, 2012 at 01:05 PM
I have to say, you are a leader in the area of practical photography, as a hobby. Rarely do I read blogs that result in: "Hey, I could do that, and probably enjoy it, if I would just and take the time to do it......With equipment I already own."
Thanks for everything.
Posted by: Wayne | November 18, 2012 at 07:20 AM
Lovely lighting there. I'm sure that security might think you're a potential thief though...
Posted by: patrick dinneen | November 28, 2012 at 12:10 PM
>>I'm sure that security might think you're a potential thief though...
Oddly enough, I've had zero problems with security personnel or parking attendants. Most guys don't question why another guy would want to take a picture of a car or in a parking garage, as long as he isn't actually touching anything. On the rare occasions when I do attract attention, I'm very relaxed, friendly, and open about what I'm doing. If someone were to ask me to stop, I would. There's always another parking garage somewhere else.
Posted by: Gordon Lewis | November 28, 2012 at 11:32 PM