The Twittersphere was a-buzz about the polarizing, digital resurrection of rapper Tupac Shakur during Snoop Dogg and Dr. Dre's headlining set at the Coachella Music Festival Sunday night. According to MTV News, the stunningly detailed hologram of the rapper (who died in 1996) could have cost from $100,000 to over $400,000 to create! [Related: Coachella 2012 Sunday: Hologram Tupac, Flesh & Blood Rihanna] While the actual specifics of how the hologram works are under wraps until after the festival...