I've got an SLR bag and a Rangefinder bag, depending what I think the subject and the occasion needs
In my SLR bag I have:
Oly OM4Ti loaded with Fuji Velvia & a Zuiko 50mm F/1.8;
Oly OM10QD loaded with Ilford Delta 400 B&W print-film with a Tokina RMC 35-70mm F/3.5 - 4.5 zoom;
Oly T32 flash;
Zuiko 135mm F/2.8;
Zuiko 28mm F/2.8;
Sigma 28mm F/2.8 with a close-up lens permanently attached to it (for close-up work);
Cheap-o-matic 2x tele-converter, which gets used very rarely but sure as day follows night, I guarantee the first time I ever leave it behind I
know I'll suddenly need a 270mm lens for that 'once in a lifetime' shot;
Cable release, lens-cleaner, cotton buds, 2 empty film-canisters; 2 spare SR44 batteries
In my Rangefinder bag I have:
Oly 35SP rangefinder with Kodak Elite Chrome 100 slide film;
Oly Trip 35 (original metal battery-less version) with Kodak Gold 200 print film;
Oly T20 flash;
Cable release, lens-cleaner, cotton buds, 2 empty film-canisters; 1 spare zinc/air 1.35V battery for the 'SP
I'll make a concious decision in advance as to which bag I'm going to take on a shoot, and usually sling my Kodak 6490 digicam round my neck as well, just in case I need it.
I also have a cheap aluminium tripod that I drag out with me for landscape shoots.
I'm looking to officially-retire the OM10QD after Christmas and get an Oly 35RC to put my B&W film in, and keep that in my Rangefinder bag. I won't sell the OM10QD because it was my father's camera (I'm too sentimental!) but I don't think I need two SLRs. With that gone, I'll retire the teleconvertor and fill the space vacated by the OM10QD with my rarely-used but useful Tamron 70-200mm F/3.8-4.5 zoom