Angelfish are about 6 inches tall and 6 inches long now. Won't grow much more...
Oscar fish is about 9 inches, possibly 10 inches. Will grow to maybe 14.
Clown loaches, largest is currently 6, but most are 4. They grow to 16 inches.
Silver Arowana, currently about 3 inches, grows to 4ft.
Edit: Largest fish I have ever kept was a Common Pleco, at 18 inches. He was sold to LFS.