The Simple Office bag from Qwstion is an excellent convertible briefcase/backpack with organization and aesthetics that fit many modern city folks.
Other Bags to Check Out:
The Daily backpack from Able Carry is an affordable, sleek little bag for daily carry.
A very sophisticated and classy take on the classic backpack, but with modern improvements for us tech-workers.
This backpack from Baron Fig is really thoughtful, minimal and useful. Lovely daily carry bag.
Smith the Roll Pack from Millican is a perfect eco-friendly rambler for daily adventures that's built excellently, has plenty of room for your stuff, but still looks good when it's not totally full.
The Velo backpack from Rickshaw Bags is an awesome, simple bag that comes in a few different sizes.