Similar to saying something is tubular. Tube is a shortform of the latter. Means what you are talking about is very unique, special, exciting, or good.
For example, one could use "Tube" in place of cool in almost any given situation:
"That new gyroball that Chris got is pretty 'Tube' eh Matt?"
Tube cannot replace cool in the following situation:
"The temperature of the air is cool" - meaning chilly or cold
"That new gyroball that Chris got is pretty 'Tube' eh Matt?"
Tube cannot replace cool in the following situation:
"The temperature of the air is cool" - meaning chilly or cold
by BJLOVE{bob} March 10, 2004
Get the Tubemug. by Kevin flet June 14, 2007
Get the Tube-in itmug. 
(noun)
A state of female sexual arousal wherein the vagina expands and elongates. This is the feminine equivalent of having the horn.
A state of female sexual arousal wherein the vagina expands and elongates. This is the feminine equivalent of having the horn.
by Sir Garence July 24, 2009
Get the The Tubemug. the act of smoking marijauna through a water cooled pipe, commonly known as a bong, preferablly made of glass and exceeding 12" in height.
At times of emmence stress and boredom, it is always fun to go tubing with your friends... and yes, it is considered a water sport.
by Eddie Torrez June 21, 2006
Get the tubingmug. Shitting into one's sock, then after, this act is done, beating another person, or persons with the shit filled sock.
by wierd235 August 28, 2006
Get the tubingmug.