BTW, from what that article says, "Ice," "tea," "DXM", "robo-tripping,", and "skittles" are all slang related to street drugs.
When the recreational drug cocktail called Purple Drank, Lean, Sizzurp, and other slang terms was first invented, it used cough syrups containing codeine. It still does - if you can get your hands on prescription cough syrup.
In one of his tweets, Trayvon asks if anybody knows how to get their hands on codeine.
Purple Drank - its influence, the 'famous' people it's killed, its influence on hip-hop 'culture', and so on, are covered in the Wikipedia article on Purple Drank.
However, not everyone can get his hands on prescription cough syrup, so there's another level of lean, purple drank, etc., made from over-the-counter cough and cold products containing DXM (dextromethorphan). The cold and cough medicines are mixed with Sprite and, for taste, Jolly Ranchers (or in one recipe common enough that it's in urban dictionaries, with Arizona brand Watermelon Fruit Punch and Skittles). Use of it slows does the world, apparently, like the codeine mixture, but DMX-based lean also can cause users to have violent outbursts. "in large doses it can result in a disassociative state, with hallucinations, similar to that produced by PCP or ketamine"'