It's been a while since I've played anything in my own draw step, but I heard a great story from Gold level pro Fabrizio Anteri, who is attending Grand Prix Los Angeles on the way back from the Pro Tour in Honolulu and it currently sitting at a comfortable 12-2 record with his controlling take on Jeskai Wins.
"I was playing a match with my Jeskai deck against a Temur deck, and at some point during the game, my opponent passed without attacking with his Elvish Mystic or Rattleclaw Mystic," Fabrizio began. "I didn't have a blocker on the table, so that was pretty suspicious. Since had Yavimaya Coast, Rattleclaw Mystic, and Elvish Mystic untapped, I expected that he would have Temur Charm in hand. If he had Lightning Strike, he would've attaked with Elvish Mystic, but since he didn't, I was fairly sure he had Temur Charm. This was my fifth turn and I was planning to cast Mantis Rider, so Temur Charm would be able to counter it. I then drew my card for the turn, and it was a Magma Jet."
Anteri could get around Temur Charm by burning an Elf in his main phase, but then his opponent would float a mana in response. So, if Anteri would do that, then he would not be able to resolve Mantis Rider in his first main phase and attack with it. Instead, he informed his opponent that he was going to Magma Jet the Rattleclaw Mystic in his draw step. Mana you tap in the draw step doesn't float over to the main phase, so this guaranteed him a window to resolve Mantis Rider before his combat phase.
The draw step is kind of an obscure place in the world of Magic: the Gathering timings. Sometimes you play Jeskai Charm on Courser of Kruphix in your opponent's draw step. Sometimes you cast Mardu Charm in their draw step in the hope of snagging End Hostilities before they can cast it. But playing a card in your own draw step has got to be the pinnacle of timing.