Phillips 66 (PSX 1.20%) and its master limited partnership Phillips 66 Partners (PSXP) have made the headlines recently, because of how high PSXP climbed during its first day of trading. It isn't the first refiner to find success with an MLP spinoff -- Marathon Petroleum's (MPC 0.35%) spinoff MPLX (MPLX -0.66%) is up more than 16% year to date -- and it doesn't look as if it will be the last. In this video, Fool.com contributor Aimee Duffy looks at Valero's (VLO 2.72%) recent affirmation of its plan to convert its logistics assets into an MLP.