I always need at least one hand for my drink. So that rules out carrying a flash in one hand.
Regarding this bracket business, you get a couple of things from a flash bracket or camera rotating bracket. One is that you can move the camera between landscape and portrait orientations and keep the flash above the camera (instead of to the side where you might get weird shadows), and most brackets let you move the flash a little farther away from the camera than if it was mounted on the hotshoe, often producing more interesting light. There are a number of favorites, as far as brackets go. I'm sure people will chime in with their favorites. I happen to have a Newton camera rotating bracket, but there are a bunch of good ones out there.
Cameras: 1DX, 1D4, 20D, 10D, S90, G2
Lenses: Canon 10-22mm, 16-35mm f2.8L II, 24-70mm f2.8L, 70-200mm f2.8L IS, 300mm f2.8L IS, 200mm f2L IS, 50mm f1.4, 50mm f1.2L, 85mm f1.2L, 1.4x TC, 2x TC, 500D macro, Zeiss 21mm
Lighting: 580EX, Elinchrom 600 RX's, D-Lite 4's, ABR800, 74" Eli Octa, 100cm/70cm DOs, Photoflex Medium Octa and reflectors, PW's, Lastolite Hilite, Newton Di400CR bracket