Just to give myself a bit of a challenge I've written a version of Paku Paku for the Commodore 64. I'd call it a port, but there is so little code in common apart from a few bits and pieces, it really is a whole different program.
Check it out on my Paku Paku C64 page.
UPDATE! 14 NOV 2012
I've added a page where you can Try the Commodore 64 version in your browser using JaC64, a Java based emulator. It's not quite as nice as running it in VICE or the real hardware as said emulator is a bit buggy, but it gives the less adventerous of you a chance to see the game in action.
Like the PC version which uses HTML and CSS3 to make a rough approximation of a Tandy CM-11 display without images, I took the time to make something that looks a wee bit like a Commodore 1702 monitor using the same techniques.