Beat The Law
Getting pulled over for a vehicle violation such as a lack of mud flaps is a pain in the rear. Permanently installing a set of ugly mud flaps is also a pain in the rear since they usually look ugly and are torn off by the first obstacle on top of that. Teraflex came up with a simple solution of removable mud flaps a few years back and they've saved us from a ticket more than once.
Hard Core
When you go to air down and find your gauge was crushed under a tire, don't despair. Pull the valve core out and listen. When you hear a whistle, the tire is at an acceptable pressure for the trail. Reinstall the core, go to the next three tires and repeat. You can get even fancier if you have a watch with a second hand. Time how long it takes until the whistle starts on the first tire, than let air out for the same amount of time on the other three. You'll be surprised at how close the pressure is in each tire.
Easy CB Antenna Mount
Rather than hard mounting a CB antenna mount to the body or bumper of your rig where it could be torn off by a rock, tree, or other trail obstacle, look in to the Kilby spare tire antenna mount. It's a great method of mounting an antenna in space that typically goes unused.
Follow The Leader
Sounds obvious, right? Keep the vehicle ahead of you in sight. Also, keep an eye on the vehicle behind you. Leaders, this is especially important. If someone has a problem, they don't always let the people ahead of them know. Trail rides are fun, but not if people get spread out all over creation, lost and angry.
Piss on it!
Not really, but that actually worked one time in the desert when water was scarce. A Hi-Lift jack is usually carried on the vehicle exposed to the elements. When it's time to use, the mechanism sometimes doesn't work. A little lubrication cures this every time, but not everyone has a can of WD-40 handy and other, heavier lubricants attract dirt and gunk, really fouling up the mechanism. Water works fine. If you're in the desert and don't have water to spare ....