I love these stories as well! The numbers on the scale don't tell the whole story, and it's nice to remember the other signs that you're on the right path.
Mine is a hill. The last time I seriously lost weight was 13 years ago. There's a 3 mile route that I used to walk every day. It includes a stretch of 4 blocks of a very steep hill. I've been working my way back towards the whole walk, and occasionally make it all the way up the hill, but always feel like I want to die by that time.
So yesterday I discovered that for the first time in 13 years, I can make it halfway up pretty easily. The last 2 blocks still hurt, but they are my next goal. I will conquer that hill by the end of September!