I've heard of using a ball of clay around the pencil, so it molds to the grip, or sticking the pencil through a squishy rubber ball and holding that. DS had teachers sending home those grippy rubber things for him all the time, and DD's teachers were concerned with her pencil grip last year in Kindergarten, but they both got over the odd grips somehow.
I know I used to deliberately use an outlandish grip at some point in grade school, and I also invented all kinds of different styles of writing over the years. Even now, if I have to write for a long period of time, I end up with a sore "crease" in the pad of my index finger from holding the pencil too tightly.
It's funny that "they say" now that kids don't really need to know how to write because they'll just be typing anyway -- my mom was told the same thing by my brother's teacher over 40 years ago! She said, just on the off chance that he doesn't grow up to have a secretary, please teach him to write anyway!
