When I was shopping for a laptop sleeve I wanted a case that provided protection but was still light and minimal. I ended up going with a neoprene sleeve. After using that for a while, I realized that is wasn't as practical as I originally thought.
With the sleeve there was nowhere to keep my charger, or any other small things that I might want to carry with my laptop. Built NY has stepped in and solved this simple problem though by integrating three different sized pockets into the outside of the sleeve. Made of stretchy neoprene, this should allow you to carry pretty much anything you need. Nice.
Available in various sizes and colors here.