I don't really have much compared to the recovery/search-and-rescue based guys, though that's kind of what I want the 4Runner to be is a recovery vehicle for the mountains where I live.
I have a 20" LED bar in front and then two 30" bars on the sides and they are meant for camping and actually had helped a lot. Usually I drive right until it gets dark and have a habit of having to setup camp in the dark, so all that actually works out well.
I have one of those car starter/inverter/compressor battery boxes off of amazon and used it a few times. It's really nice to not have to pull out jumper cables, just pull the portable power out and hook it up.
I have one of those flat box tool kits with the two fold out doors with full wrench, star, allen, screw drivers, metric/english, etc. I have a 4lb hammer, WD-40, degreaser, a full crimp tool set and electrical tape and 20' of 14 gauge wire, shop towels, that citrus smelling hand shop hand cleaner, a box of brownies (legit), a 34mm socket or whatever is needed to pull a CV (though I don't have spare CVs...). Then four ratchet straps, bungy cords, a 6' and 10' tow strap, a kinetic recovery strap, a 22 caliber Henry Survival Rifle and ammunition and cleaning kit (the rifle unbolts and slides into the stock which is waterproof and floats as well as holds three magazines of 8 rounds), 5 gallons of water, a sleeping bag, a hi-lift, duct tape, flares, winch, jumper cables, hitch clip assortment, CB radio with 4' antenna, fire extinguisher, survival knife, lighters/matches, etc.
I think that about covers what I have besides some miscellaneous other stuff. I have a 3'x1.5'x1.5' plastic box in the back of the truck that holds everything minus the water jug, power unit, and tool case. And the toolbox and plastic box are strapped down to the rear mounts with two of the ratchet straps. Essentially everything I buy at school to fix things that comes up gets thrown in there. I figure it's enough stuff where I can survive for an extended period of time if I get stuck somewhere, and then plenty of items to get me unstuck or signal someone. This is all the stuff I carry with me all the time.
The one thing I'm really missing is spare gas cans, but I don't want the truck to smell like gas. I might get some low profile cans or if I get a rear tire carrier then will mount them. Dual batteries would also be nice and soon I'm gonna get the tools so I can weld with batteries on the trail and lockers next year. Love to hear what other people run so I can add!