As a street photographer, my philosophy has become if it can’t fit in my pocket it’s not worth bringing. You’ll notice quite deliberately absent from my photograph is an actual “camera” bag, that’s because I don’t carry my “cameras” in a bag, I put them in my pocket.
In fact there is only one item here that traditionalists would even consider a “camera” and that’s my trusty Ricoh GR Digital. It doesn’t get a lot of use as my primary camera is my iPhone, but I bring it with me and use it usually for low light situations where the iPhone just won’t work. I love its sharpness, clarity and specifically the quick snap shutter that surprisingly doesn’t have that horrible shutter lag of most point and shoot cameras and that’s probably the main reason it stays in my back pocket.
Yes, I carry three iPhones with me at all times. I really don’t see it any differently than a photographer who carries a few bodies with them on assignment. Not to mention, they range in model and actually have very different characteristics. I love using my iPhone 3G as kind of a digital Holga.
The other two cameras the iPhone 5 and the iPhone 5S actually have a mobile phone feature which I find quite convenient for camera, :-) I generally carry two simply for backup reasons and while I have extra battery packs, like the Mophie, I actually prefer not to carry those and just carry extra bodies.
Finally, the newest edition to my camera kit are my Google glasses. You can call me a Glasshole, I don’t really care, because having a camera basically mounted near my eye that snaps when I wink is just f’ing awesome. I generally don’t wear them in social situations and have found them extremely useful for snapping images on the street. The quality is actually surprisingly good despite a lower megapixel count than an iPhone.