Maybe MDMA won't put you into a coma, but Ecstasy might. Let me explain.
Ecstasy is supposed to be drug slang for MDMA. I say "supposed" because E is (or so I'm told, ahem) not just for Ecstasy but also for Expensive. In my hometown (or so I am told by various deranged substance abusers), a pill of E costs $25 to $30.
This naturally includes a fair profit margin. More than one unscrupulous drug dealer has realized that if he adulterates MDMA with some other, cheaper, substance that kinda sorta feels like MDMA, he can expand that margin even further. DXM is one common adulterant of E; I have also heard of 2CB being used.
The upshot of this is that every time you take that tiny little pill, you are playing Russian Roulette with your one-and-only brain. The e-mail transcribed in AmadeusTheKitten's writeup may be 100% truthful and correct. Who knows what this dumb kid really took?
Dr. Timothy Leary was once invited to testify before a Congressional committee on drugs, headed up by Teddy Kennedy. The subject, naturally, was LSD. Despite Kennedy's repeated attempts to trip up Leary and get him to say--on the record--that LSD is dangerous, Leary stuck to his guns. He said that the manufacture, sale and distribution of LSD should be legal but carefully monitored by the government--because otherwise "you do not know what you are getting."
Now, the good news. There are organizations such as DanceSafe which sell Ecstasy testing kits. These are little kits of chemical reagents that react a certain way with MDMA, another way with DXM, yet another way with 2CB, and so on. The Federal government has already tried several times to legislate them out of business (such as with the criminally unconstitutional Methamphetamine Anti-Proliferation Act), so if you like your E, I suggest you stock up now. And keep an eye on the government; if they try to pull that shit again, tell them to knock it off.