There's a Ruby's Diner at the end of the pier in Huntington Beach:
http://maps.google.com/maps?client=s...w&z=16&iwloc=A
A little pricey for general diner food, but a unique view.
You can also grab a frozen banana on Balboa Island in Newport Beach:
http://maps.google.com/maps?q=frozen...07982&t=h&z=17
Unfortunately, no Bluth's Banana Stand.