Hey, I've been all around trying to find a rugged unlocked clamshell phone for my dad. The man just kills phones so I thought either mil-spec or cheap, but I'm not having any luck. Figured this was the best place to ask for suggestions.
The Samsung Rugby or the Motorola Tundra are your best bets for GSM handsets. Both are sold through AT&T although I'm sure you could find an unlocked one somewhere out on the internet.