I'll have to try ROK straps.
Coming from a canoeing background, I have a wide assortment of canoe tie-down straps from
National River Supply, NRS, available in 1, 2, 3, 4, 6, 9, 12, 15 and 20 foot lengths. I find them very handy for strapping things everywhere, but especially to my motorcycle and roof.
But one of my favorite places for straps is
Andys Strapz. Andy has a wide variety of straps, and also bagz. I have a tank bag and a seat bag from him and I really like both.