I have canine working experience and I would not count on a strobe light to stop a dog. It can be a deterrent against some curious dogs or dogs that are not wound up and ready for battle. A dog that is attacking is acting on instinct, and instinct usually overrides everything else.
I fully agree with GreySave. In my experience a really bright light can reduce a dog's confidence a bit and in some cases might be just enough to make fear override its curiosity. Against a well trained dog...forget it. Fortunately we're not talking about well trained dogs, unless you're a criminal and instead talking about rogue or unsupervised animals.
I've fired practice taser cartridges at cardboard before, but I can't imagine how nearly impossible it would be to score a taser hit on a lightning quick animal in attack mode. Honestly, it would be one of the last weapons that I'd want. Neither would I want a hand held stun-gun because if the close proximity that it puts your extremities within inches of bone crushing rows of teeth, not to mention that it may or may not have the desired effect. If a vicious dog is within that range I'd much rather be wielding 9 inches of sharp steel. As a dog and animal lover the last thing I'd want to be faced with would be permanently harming or killing a dog. This brings me to one of the only non-lethal, yet fairly reliable deterrents that I've used for about 20 years, pepper spray. I've had great results with it while mountain biking and the best part is that it doesn't require great user skill, precision, or even speed. I routinely carry three different sizes, depending on the outdoor activity. My smallest is an ASP Street defender (15 grams of propellant). My medium size is Police Magnum w/jogger's hand strap (2.0 oz of propellant). My large size is Pepper Power, bear spray w/belt case (9.2 oz of propellant). The larger the volume of spray the more "stand off" distance it provides but just as important, it can be much more forgiving for the user. For someone needing a general purpose defense spray where size and weight are not critical, I'd highly suggest a 7.0 oz size fogger or larger. They put out as much in a half second as the ASP Street Defender has in its entire capacity and provide an honest 20-30 foot effective range. The large cone shaped stream covers a wide area quickly and can even form a sort of airborne barrier for a few seconds depending upon wind conditions.
I've emptied 6 or 8 key defender cartridges, both practice and actual pepper, and several 1-2 oz prays of varying types. I've emptied a 9 & 13 oz canisters also which was very impressive. Trying those live is what convinced me to use the largest spray that I can carry in a practical manner. They are impressive to users who've only experience using key or purse sized sprays. Most of the larger "foggers" were designed and formulated to repel bear but they work equally well on any animal with eyes, respiratory system and mucus membranes.
Would I rely solely on defense spray to protect me from something that had the capability to kill me?...no way. I still carry a last ditch means should I ever find that my first line of defense didn't work. Obviously, everyone will have to decide for themselves whether or not you'd be capable or willing to protect your life futher if pepper spray doesn't work.
