Lift-off help, redesigning how a rocket does it (Score 1)

One thing I've wondered is, the initial liftoff is the most energy-wasting part to get a rocket moving, why haven't they designed a "tube" to fit around the rocket to catch the gas pressure and literally "pop" the rocket upwards faster? I was thinking they could either put the rocket on an elevator down into a hole, or bring a structure to surround the rocket and have a skirt at the bottom to keep the gases confined below the rocket until it clears the structure, and that way use the build-up of gas pressure to force the rocket upwards faster initially. Seems to me if it's gonna spew all that exhaust out, it should be able to use the gas pressure for something other than a big fireworks display! Hurrah for SpaceShipOne, seems like a better way to boost into orbit than Supersized missles. Keep up the good work, Burt! - Jerry -