For D&D, I use the "Ultimate Character Sheet" Mad Irishman made for Necromancer Games. For Iron Heroes, I made my own sheet because the one included in the book was way too small (if you have a class in the game that can have 30 skills maxed out with only a little powergaming, 12 write-in slots for skills is NOT enough). I then noticed that my sheet had too little space for feats and class abilities, so I made a new one.