I wish I could say "I knew these guys way back when...", but I can't. Instead, I discovered Nuttin But Stringz the way many other people did- through Jack's big Music Show on Noggin. NBS consists of two brothers, Damien and Tourie Escobar, from Queens, NY. They're formally-trained violinists who combine classical music with jazz and hip hop. My 2-year-old loves this song, called "Thunder".
Find out more about Nuttin But Stringz on the group's Web site and on the wikipedia page.