Check out Corki. His Passive allows him to deal significant magic damage as well as being a somewhat caster-style ADC weaving AA's in-between his casts with Trinity Force. You can also build him AP and go for massive amounts of poke, however his ratios scale better with AD. That being said, Sorcerer's Shoes are always a great pickup on him. He's also 3150 IP to save you a bit. He fits well into Mid or Bot, however he doesn't do so hot in other roles. He's a big bully in lane as well. His Package (an additional perk of his Passive) allows you to have essentially a Rumble Ultimate every few minutes and initiate/disengage very well on him.
Ultimately, I'd say it depends on your playstyle. If you're looking for a pure mage I'd steer away from him, same for a pure AD. He doesn't have the team-wide melting potential of someone like Ashe, Vayne, Sivir or Kog'Maw, and lacks any form of Hard CC like most mages (although he does have a moderate disengage on his W) so he's in a niche spot of his own requiring you to be very attentive to both your position as well as your enemy's.