For me, one of the joys of climbing has been pushing my limits, not merely reaching them, although perhaps this is just semantics. In any case, I have reaped some of the greatest rewards when I've climbed something that a only few years prior had seemed impossible, or at least quite improbable, for someone of my limited talents. This has been an experience I've had on numerous occasions, and it has been just as sweet each time. It has taught me again and again to keep my eyes open to possibilities. There must be more that seems out of my reach that really isn't.
For me, none of this has had to do with altitude per se. I've hiked up a couple of the easy 20,000'+ trekking peak bumps in Nepal, but that seems attainable by anyone with a healthy pair of lungs, a few thousand dollars, and the time and inclination to go. The altitude itself was not a big deal.
In terms of altitude, I'm more interested in how high I can bed down an attractive member of the opposite sex. So far, I haven't managed any higher than about 11,300'.
What's your record?