I'm pretty amazed that of all systems, Game Boy stuff from Game Boy stone age to Game Boy coke mirror is holding value. I'm talking about software here, kiddies. Game Stop gives $5+ for everything outside of ultracommons, and original game boy titles sell for double digits.
I can't say I'm surprised, but it is remarkable. I would have expected to be rejoicing in showers of original game boy games for $1-$4...
I can only hope for a lack of backward compatibility in the next gen handheld system.