are you talking about flex shaft needles?
for lack of a better picture...
like the ones on the end? If you are they are basically just a regular knitting needle but you get the same benefit of knitting flat with circs in that you only have needles as long as your hand so that motion created by the long needles isn't there. i love them except that i tend to drop them more just because i play with them in between rows when i get distracted by whatever movie i am watching. I think they are great though!
ummm...but if this isn't what you are talking about...never mind...pay no attention to the girl behind the computer screen...