By Felicity Clarke, Contributing Reporter
RIO DE JANEIRO - When a Carioca friend tells you not to be scared before getting out of the taxi in an unfamiliar area in Zona Norte, you can be forgiven for thinking you’re going to encounter formidable men with big shiny guns.
As it turns out, the potential fear factor in a cluster of streets at Praça de Bandeira is not the roar of gunfire but the earnest roar of black-clad rockers with studded belts and surly faces yelling along to German metal band Rammstein.
Every weekend, this unremarkable, slightly shabby area . . .