Found these on a forum:
First, Zack Kim using hammers-on on two electric guitars:
{YOUTUBE:aZpD0btOZx8}
Next is Jean Baudin playing the theme on on an 11-string bass:
{YOUTUBE:yf56jYDv2fc}
The above two are great, but my personal favorite is Sebastien Gomez playing the Mario theme in classical guitar style:
{YOUTUBE:YQcuQsD587M}
That's the one I want to learn how to play!
