I hate feet and lower legs, and they hate me right back, which is why most of my characters wind up wearing big baggy pants, with big blocky shoes!
Also, when I draw my lead character (she's the one over in that "help me name my character" thread) I tend to mess up the head-to-shoulder/upper torso proportions; IE: Her upper body is always a little on the small side.
Here's a link to my Deviant Art page and an excellent example of this problem:
Fictional Japanese Girl 1 by ~Th4rlDEAL on deviantART