Like many my age and younger, I was diagnosed with ADD as a child (I'm 32 now) and went through the entire gamut of meds (stimulants, tricyclics, SSRIs) before discovering that norepinephrine seems to be the culprit for me. I have a very difficult time coding when I'm off the meds (I can do it, it's just difficult to keep the data structures and control flow in my head). I took atomoxetine for several years and it worked wonders, but it caused severe side effects that I wasn't willing to put up with. I've since switched to buproprion, which isn't quite as effective, but otherwise doesn't give me any problems. The most general way I can describe the difference between being medicated and unmedicated is "sharp" and "dull", extremely so.

I have a friend that says if I can't do my job without medication, I'm in the wrong profession. He may be right, but I love working with computers, and I don't have that passion for anything else, so I'll keep taking the meds. I'm no longer interested in debating the ethics, since for me it really is the difference between high performance and average performance, and there is no reward for average.