I have a couple "HHKB" layout boards which do that. It is quite helpful!

What I have found even more useful is triggering a "layer" when Caps Lock is held down, which turns H, J, K, & I into an arrow cluster; U & O into Page Up / Down; and P & ; into Home / End. To toggle regular Caps Lock, I just activate the layer and then hit A. It's a big time saver! :)