Have a tarp in your BOB. Not only does it mean you can make a quick shelter secure from the rain, but you can also make a solar still http://en.wikipedia.org/wiki/Solar_still which everyone should know how to do.
 
Also space blankets not only compact tight for travel and keep you warm, they also all but erase your thermal signature.

If you want to have some small items with you, as a pocketlamp, a magnesium stick, a lighter, a short pen, a small knife and so on, and you  
don´t want to use your pockets or don´t have pockets; use a small bag for mobilephone/cellphone with a carabiner on. Now it look like you have a cellphone hanging but you have a useful kit with you. Have one myself and have had use for it many times. And I have surpriced people when I quick can get a lamp or a knife..
 
The best kit is the one you have with you.
 

Caldou means that he thinks it's abad idea for others to post in this topic with their survival tips. He thinks it would be better if people would PM you their tips for you to post. That way there will only be 1 survival tip posted each day by you, and the thread will stay active longer.
 
P.S.- My survival tip: never call your immediate superior at work "bossman" to his face.

 Well since there isn't one for today: As soon as you kind of have your bearings and have realized you are in a real survival situation one of the first thing you should do is make a Rabbit stick. It can be any where from 2ft-3ft long, have iterring on the short side if you are in dence woods, and a comfortable thickness from 1-3in preferably with a slight curve. You can also whittle down the handle a bit if you want it to be a little thinner.  
 You now have a self defence tool, digging stick, tool for gathering wild edibles by digging or nocking them out off trees, baton for splitting wood, and as the name "Rabbit stick" implies, hunting. When throwing it's almost always best to throw side arm but sometimes if say you have a squirrel up in a tree you can throw overhand as well. Possible game are ducks (and gesse if you can throw hard enough), squirrels, groundhogs, doves, Rabbits and pretty much any small game you within your distance. You might want to practice a bit before you are in a survival situation but the learning curve for throwing one is pretty short. Multi purpose and easy to make and use are some of the top features you should look for in make shift survival tools, one of the best being, The Rabbit Stick.

OK Survivors, today's tip comes from ol' SlingBadger from out there in Akron, NY here in the good ol' USA and SB say's:
 
  "OK, take a regular straw, then fill it full of rolled up cotton gauze that has been covered  in petroleum jelly. Seal both ends with a lighter. These can  be used for firestarters. They can be cut up, or used all at once. Also, because of their size, they can be put almost anywhere for convenience."  
 
  A big thankyou and shout out to SB as well as Dan, Ulrica, PerpetualStudent and Ahaw from the boys (and girls) here at slinging.org and remember Survivors "If you ain't a Slinger, you ain't"
 
                           Fletch_Man out.

Quote from perpetualstudent on Mar 22^nd, 2012, 4:42pm:

   This is an excellent tip.  I can't tell you how many rainy camping trips were rescued due to tarps.  If you're living outdoors for any length of time then no matter what the season a tarp (several are better) is an absolute must.  Having some dry space to operate outside of your shelter, be it a tent, camper, truck or whatever,  can make all of the difference in the world.      
    A wooden spear with a fire hardened point and a rabbit stick are very useful and easy to make and carry.  I would have both.  

I like the straw idea. Keep 'em coming.