Phillips 66 (PSX -0.85%) and its master limited partnership Phillips 66 Partners (PSXP +0.00%) 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 -0.85%) spinoff MPLX (MPLX +0.79%) 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 +0.34%) recent affirmation of its plan to convert its logistics assets into an MLP.