I just started using Isacord after taking a Leah Day class on Craftsy.
Leah sells it on her site at $6.00 for 1,000 meters (1,093 yards). You can find it from other places in a 5,000 meter spool and sometimes on sale.
Even at $6.00 for 1,000 meters - that is 0.005489 cents per yard.
I like that there is no lint like the cotton Gutterman I was using.