I just listed the ones that Riot put "carry" tags on. I would add Warwick, Teemo, Gangplank, Corki, and Nasus as heroes capable of being built well as a physical carry. If you're extending your notion of a carry, then it's a whole different situation.. I try and keep the idea of a nuker and a carry seperate as much as possible. Anivia, Fiddle, and Karthus would all fit the idea of a caster carry. I didn't include Veigar or Annie since they're for burst. These ones are pretty good at keeping up the dps for the duration of most fights.

AP Teemo is really a better carry than physical Teemo. Unless, for some reason, some people think Carrys are just champions that get powerful autoattacks when well fed? A well fed AP Teemo, which isn't hard to do if you know how to play him right, will have insane, reliable burst, allowing himt o pick off targets in teamfights and ganks while also having deadly shrooms, and the potential chance to deal incredible damage to an entire team.