An urban beam is associated with older people aged above 40 years of age. It is an imaginary thin beam like shape located at the centre of a person's upper body and the term is used when a person of an older age understands and genuinely takes an interest in modern urban activities such as breakdancing, beat boxing, graffiti art and various other things. These beams light up when these people see these types of activites which they enjoy greatly.
Person 1 - Did you see that Piers Morgan on TV last night.
Person 2 - What on that show Britian's Got Talent?
Person 1 - Yeah, did you see those breakdancers
Person 2 - No but did the judges like them
Person 1 - They liked them a lot, but not as much as Piers. His urban beam was shining bright so they must have been good.