Here's a photo of a couple of my best scars. The one near my index finger knuckle is from slicing my hand open by accident with a box cutter when I was 11. We had just moved, and I was trying to help unpack boxes... 4 stitches for that one. The scar used to be more defined, but I happened to skin that knuckle pretty bad one day and, interestingly enough, I was able to remove a lot of the scar tissue. When it healed up again, the scar was much flatter than it was previously.
The big one on my wrist is from about a year later when I was out "street luging" with my friends (aka laying down on my skateboard and riding feet first down ridiculously steep hills). I lost control of my "luge" and hit the curb with my arm, grinding the skin down almost to the bone. The scar originally extended all the way up my forearm, but that part has faded away over time.
I also have a scar about an inch long on the back of my left calf, no clue how I got that one. Oh, and I have a nice big one on my right index finger from when I got bit by a skink. Sheesh, I have more scars than I thought...
Thankfully, I haven't received any serious scars in recent years, and none from climbing. I narrowly avoided needing back surgery when I fractured my L1, so no climbing scar stories from me :P