A weapon that is often employed by someone who is "new" to an FPS game and needs to use the maximum ammount of fire power just to "try" to survive, because noob's have no skill. Usually a Bazukka or rocket launcher. Hense the term "noob tube".
Maj. Poopinschaft: " Hay you killed me 10 times in a row....
I think I'll get you with a bazukka, because I have no skill ! "
cartOOnman: " Go ahead, Get your noob tube, I'll still bash you over the head with a 45. NYUK NYUK NYUK MUUhahahahahaha "