I've heard of them only from an old TSW mag.
Sunday, January 7, 2007 - SINED-jas attack Team Challenge
This year for the Transworld Team Challenge the SINED team went as SINED-jas (ninjas). Held at Buttermilk this years event was nice, lots of teams, good costumes, and lots of sick riding. SINED-jas were fully equipped with num chucks, stars, boom box blasting kung-fu fighting and Vanilla Ices theme from Teen Age Mutant Ninja Turtles "Go Ninja , Go Ninja, Go", and big smoke bombs. The smoke bombs ended up what everyone remebers, one night at the hotel bar one ended up going off right in the lobby, well Transworld got banned from the hotel for life, and the rest of the event the saying was " those god damn ninjas".
Anyway we ended up getting 2nd for costume (again) and Pat Milbery won special feature. Over all a good time. Look for it in Transworld Feb issue.