2Pac & Snoop Dogg, "Hail Mary" and "2 of Amerikaz Most Wanted" ("Live" at Coachella 2012)

If you have been living on the bright side of a cave the last few days, you've likely already seen this (or at least heard about it).  Still, it deserves its own Tuna Day.  How far we've come since Leia's plaintive cry for help.
 

Deltron 3030, "Positive Contact"

From their eponymous debut album, released 11 years ago, here's Del tha Funkee Homosapien, Dan the Automator and DJ Kid Koala...  Step into the future, ladies and gentlemen.