My favorite bag depends entirely upon what I happen to be out shooting with: the Hasselblads travel in a Lowepro backpack; the Linhof in a backpack that I customized myself; the Nikons go out in public in a Domke journalist's bag; and the Leicas - depending on the weather - generally travel in the pockets of my jacket (35 and 90mm lenses) and around my neck (the trusty M6).