I am a litigation attorney. As a strong introvert I hate small-talk but get a thrill out of substantive presentations in court or at conferences. Arguing a case in court is like motorcycling - your sense sharpen, you feel a high level of focus, and all the external brain clutter and worries just go away for the next hour.
Of course, an hour of argument may require ten hours of tedious preparation, which is not nearly as fun!