I swear to God Tobi is my beagle... He is pretty awesome, and it is totally believable that someone on the interwebs had heard of him - thus prompting the OP's question. Accordingly, I am very confident in my win. Give him some peanut butter and he is your best friend!
Think of how happy my beagle would be with my avatar dressed up as master chief. *wink wink*
The only other Tobi I can think of is this guy I work with, but his name ends in a "y" - as in "Toby"...and he is kind of a dick. Last week he stole my can of Pepsi out of the fridge at work. He never owned up to it, but I know he did it because I saw an empty Pepsi can in his trash can. Very suspicious. Just throwing it out there... :>
Google says Tobi is Uchiha Obito though...