Are some of these questions too difficult...
 

To use as human verification on sign up/search/contact form?

A few examples of possibly too difficult questions from my forum:

Quote:
In Super Smash Bros Brawl, what characters from The Legend of Zelda are playable?

Which Nintendo character says 'FALCON PUNCH!'?

What game is Geno from?

Which Donkey Kong character makes his first Mario Kart appearance in Mario Kart Wii?
According to some of the moderators, these might be too harsh and be partly responsible for causing quite a few less possible registrations, but they seem extremely effective in keeping out the standard spambots and sweatshop spammers.