In my time I've owned a lot of photo kit, too much photo kit. I've boiled my everyday camera bag down to what I consider the minimum, less kit to worry about seems to help me actually shoot.
I wonder what other FMers consider their absolute minimum everyday outfit allowing them to take the majority of images they want to make?
On my 7D and 5D2 my minimum rounded outfit is:
24mm f1.4 L Mk 2 (Night photography)
24-105 L (General photography and portraits)
135 L (Portraits and night sky photography)
One camera one lens everyday kit would have to be my 6D with a 17-40L... a nice light setup easy to carry around, on days when I know I'm going out shooting after I work I'll add a Sigma 12-24 (or 24-105 depending where I'm going) into the mix, and if I'm out shooting with friends for the day I'll throw in the 24-105L
My minimal outfit for daily carrying is the 400D and 24-85 USM. These are both silver versions so this kit appears as some bridge camera at first sight
However, since 400D goes up to ISO1600 max and it isn't particularly good at it there, I also carry 35/2 as a compromise between lens speed, usable FOV and lens size/weight.
Occassionally I take 220EX flash for minimalistic trips. The smallest flash with the red AF assist.
I shot weddings for years with a 16-35L II, 50mm 1.4 and 85mm 1.8 on a couple of 5Dc's. I'm now out of weddings and pretty much living with my 5D3 and 50L that I carry everywhere.
I could live well with my 5DIII, 35 1.4 , 70-200 2.8 8II, and a 2X III Extender and Tamrac sling bag.
The next level up would include 100-400, 100L Macro, and 600EX flash.
The 24-70 2.8 II accounts for nearly 85% of my photos which I carry with a small on camera flash in a light weight hikers grade fanny pack. If I am in a park, then I have my 400mm DO (+/- 1.4x) with a G3 & 20mm pancake so I am not dropping my lenses all over the place. That's probably another 10%. The G3 is fine for casual use and plays an important role for me, but it is too slow for regular use. I use my 70-200 at times (mostly locally), but if packing is tight, I leave it. I have a vixen polarie, so once I pack that, I can't always bring the 70-200mm which I should probably use more for landscapes than I do now.
For me, the 24mm 1.4 II has too much coma for night sky photos, so I use the 24-70mm, sometimes with a tracker. I had the voigtlander 20mm pancake which I loved until I started with night sky photos - its coma is even worse. I'd love to have a zeiss wide angle but I just would not use it enough and I'd run out of room in my carry on pack as well.
This is a complex question, and the answer depends on a bunch of stuff - what you photograph, what you regard as minimal, what you intend to do with the photographs...
A minimal full frame kit based on my 5D2 might also include:
* just a 50mm prime, for certain types of street, event, etc photography
* 24mm, 50mm, and 135mm primes (or swapping out the 24mm and 135mm for 35mm and 85mm)
* just the 24-105
* just a 100-400, for certain types of wildlife shooting
For me, though, a full frame DSLR is no longer the basis for a "minimal" kit. I'm also using a Fujifilm X-E1 for that purpose now - a fine cropped sensor, mirror less, "rangefinder style" camera. Here a minimal kit might include, in addition to the camera body:
* a 35mm f/1.4 lens, or
* a 14mm f/2.8 lens, or
* a 18-55mm zoom, or
* the first two lenses in this list
This is way smaller and lighter than any DSLR based kit that I can put together that works as well.