The Colca Sac line of protective sleeves are handmade by elves (just kidding–at least I think I am) by Zagora in Salt Lake City, UT USA. The product line includes covers sized from iPhone up to a 17 in MacBook Pro. This review is for the 15 in MBP model.
The sleeve is made from hemp based fabric and lined with cotton fleece. Closure is by velcro tab, and an exterior pocket provides a handy space for stowing small objects, though a test fit with the Apple Wireless Keyboard worked fairly well.
The sleeve seems to be made with quality materials and fit and finish are good. The fleece lining provides substantial cushioning during storage and transport, another plus. If I carried my MBP in a backpack I would definitely use this sleeve for the added protection.
Not many come to mind. It is, after all, a protective sleeve and it seems to fulfill that function well. My only caveat is a suspicion that the fleece lining may not keep its pristine appearance long with exposure to the environment.
A well made product worth a look if you are in the market for a protective sleeve.
At $40 USD for the 15 in MacBook Pro model it is perhaps a little pricey, but a lot cheaper than repairing or replacing a damaged Mac.