
sometimes the use of fill flash can help you out tremendously in harsh lighting conditions, or just provide the extra kick for the look of your pics… I started out using an off-camera cord, but hated every second the logistics of it, so…
option #1 off-camera flash cord, which is a pain in the ass to use, I always I feel like I’m trapped and can’t move around freely ($74.95 for the canon model one I use). there are cheaper alternatives, but I happen to shoot Canon when I’m not using the M9…

option #2 Pocket Wizards, fairly expensive at $169 for the Plus II and $295 for the Multimax, but granted, they can do wonders for commercial and studio work, but just don’t fly in the street (matter of fact, they will go flying out of your hands, as the receiver needs a hotshoe adapter/cord and some creative rigging with rubber bands, velcro or whatnot). besides, they are ridiculously big on a… you will also poke your eye out with the antenna. the newer, smaller versions are supposedly just as good though.

option #3 is pretty kick-ass: Cowboy Studio radio trigger, basically a radio trigger without the frills, or the size of Pocket Wizards, small, cheap and it works like a charm, opposed to the wireless triggers one can find on ebay. ack.
I’m using a Canon 430EX in manual mode, mostly @1/32 or so, but I also have a bunch of old school Vivitar 283′s ($30, tops) with the additional Varipower module, which allows to dial the power down to 1/32 for fill. the newer Vivitar 285 has variable power built in.
another really cool thing about the Vivitars – there is an accessory to plug them into the wall, which is awesome for on-location shoots. and a battery pack, which I never bothered to get… at low power the 4AA batteries will last a long time.
and yes, I pointed the flash towards the ceiling for effective fill and to avoid flare shooting into the mirror. in the streets that thing is in your face and works like a charm…
purchase the gear on amazon:
Canon Speedlite 430EX II Flash for Canon Digital SLR Cameras
PocketWizard 801-130 Plus III Transceiver
CowboyStudio NPT-04 4 Channel Wireless Trigger
PocketWizard MiniTT1 Transmitter and FlexTT5 Transceiver for Canon DSLR Bundle
Canon Speedlite 580EX II Flash for Canon EOS Digital SLR Cameras
PocketWizard PW-MMAX 802-450 MultiMAX Transceiver