hogback
noun hog·back \ˈhȯg-ˌbak, ˈhäg-\

In geology and geomorphology, a hogback is a long narrow ridge or series of hills with a narrow crest and steep slopes of nearly equal inclination on both flanks.

What if you have half a leftover ball of stripie yarn?

Maybe you knit up a checkerwork hat and now you have half a ball left?

Needles: Size 1.5 to 3 or 2.25mm to 3mm needles, please check your gauge before you start. You may want to use a smaller needle size for the brim.
Yarn: approx 200 yards
Gauge: 8st/inch
Notions: a stitch marker, scissors, yarn needle or crochet hook