[jcagalawan]

Octopuses is valid. As is octopodes, but octopi is a freak Greek-Latin hybrid by people trying to convince the world that they aren't idiots but is now also valid.

[1] http://www.youtube.com/watch?v=wFyY2mK8pxk

[zem]

and yet "octopi" is the most euphonious of the three, and deserves to win for that alone if nothing else.