I'm search for a backpack that I can bring to work, but also carry enough clothes in for weekend trips. Ideally, I'd like something with a separate laptop compartment. Black or blue preferred, but not required.
If you're willing to go with a roll-top bag, the Spire is fantastic. It's got a laptop compartment that fits 15" laptops and enough space for a few clothes, though you probably couldn't fit those and an extra pair of shoes.