I remember hearing that sh*t around 2002...and the first person i remember doing it was Rodney Jerkins aka Darkchild when he put the tag "darkchild" in the beginning of that Brandy song "What about us"...But he's R&B.... a few months later I heard "Just BLAAAZE!" on "Oh Boy and "Pump It Up".....This would open the flood gates for other hip hop producers to do the same, From "al al al alchemist" to "Jahlil Beats Holla At Me" I say it was Just Blaze but I could be wrong. If I am I would like for someone to correct me.