today, one of my friends brought in an old puzzle that was a bunch of yellow and red cubes attached by a single string. Does any one know what this is called? It's supposed to form a cube when solved

A Kibble cube?
http://twistypuzzles.com/cgi-bin/puzzle.cgi?pid=958

It's called a snake cube. There are three possible arrangements of the cubes as far as I remember.

nope it was different.

Different to the Kibble Cube?
Different to the snake cubes?
Different to both?
More info please or we can't help you.

different to the kibble cube, didnt see the other comment, probibly posted at the same exact time, sorry about that

No, there's two days between the dates on your post and the snake-cubes post. And you still didn't answer the question. Is it a snake cube?

I have two puzzles similar to what you are describing:

They form a 3x3x3 cube, and each segment has connections at two sides, at either a right angle or straight through. Each connection can rotate freely, and the string connecting them is elastic so you can work with it. Here's some cell phone pictures, perhaps this what you mean?

Dave

THAT"S THE ONE! thank you!