The tactical folders most often used by todays service people include any number of Benchmades automatics, Bucks Strider, Columbia River Knife & Tools Kit Carson M-16, and Spydercos Military. Many selected the CRKT M-16 because of its open-channel construction, which makes cleaning the knife easy. All of the preceding folders meet the servicepersons needs and are available through the Post Exchange system.
Special Ops personnel are more inclined to buy premium knives. One of my sources prefers the Chris Reeve Sebenza for its obvious quality and cutting ability, because its simple, open-channel construction makes it easy to clean and, most importantly, because the Sebenzas frame lock ensures that the knife will not close on his hand as long as he maintains finger pressure on the grip. Another has carried an Emerson CQC-7 for years and says that it has served him well. A civilian security contractor carries a Randall Model 14 on his web gear, a Strider folder in his pants pocket, and two Spyderco Crickets clipped to his underwear--this in addition to two handguns and his primary weapon.
Most enlisted personnel carry a multi-tool. Gerber and Leatherman seem to fill this need about equally. Though the tactical folder has assumed the role of daily using knife, fixed blades are still important gear for frontline troops and Special Ops personnel. Few, if any, support personnel carry fixed blades.