A drop or two on the teeth of vice grips, pipe wrenches, pliers, etc. will multiply the gripping force of that tool.
When using a power driver, it's very important that you wiggle the screw bit with pressure, once again to be sure that you get a good bite prior to giving a burst of power.
E-Z Grip is also excellent to use as a preventative. Use a drop when inserting a new screw to help prevent slippage and damage to the fastener. It also reduces the wear on the screwdriver bit.