I've been thinking about it using Metallo in a fan fic and I keep thinking about Sam Worthington in Terminator Salvation and who his character really was (sorry but him just randomly becoming a good man from being a convict killer is crap), maybe a little re-working with it and he'd actually be perfect to play John Corben in a live action movie with similar effects to him in T4 (but with alot of green lol).
Then after words I found a bunch of fan casts that had him too lol, so yeah....just throwin that out there