Bite and sting protection is a must for your trip into the woods. I never thought about this before. Until I took a 14 mile hike one day by myself, and came out of the woods with over a hundred "friends" attached to me.
When you are out in the wild, a must have in your survival kit is a fire starting device. It looks cool when Bear Grylls starts a fire rubbing his calloused hands on two sticks for hours, but wouldn't you rather just make one or two strokes of your fire steel and relax?
If you go out for a hike and don't take a survival kit of some sort with you...for shame. Make sure you have the best chance to return to your loved ones by taking a prepackaged survival or medical kit with you on the trail.
Ok, so maybe you won't need a saw in a survival situation, but if you ever get stuck in the wilderness don't you at least want to try to build a Survivorman style condo out of some sassafras and birch?
Another inexpensive, yet lifesaver of a device for your survival kit is the signaling device. Whether you carry a signal mirror, emergency whistle, or just have a bear bell to alert you of a hungry intruder; there is no reason you should not be rescued.
A knife is a great tool to have in your kits when camping or hiking. You might as well buy one with some survival features built into it.
Every survival expert will tell you that water is crucial for any survival situation. Whether you are in the desert or frozen tundra, clean drinking water is an absolute necessity if you are going to survive.