Comcast/Xfinity OnDemand has several WWE Summerslam related items available at this time. They include…

2013 Preview (Free):

The Best Vs. The Beast

SummerSlam preview music video

SummerSlam Reach For The Stars video

SummerSlam All Access

SummerSlam All Access En Espanol

Classic Matches (Free):

SummerSlam 2004 Edge vs. Batista vs. Chris Jericho WWE Intercontinental Title Match

SummerSlam 2011 CM Punk vs. John Cena WWE Championship Match

SummerSlam 2009 D-Generation X (Triple H and Shawn Michaels) vs. Legacy (Cody Rhodes and Ted DiBiase)

SummerSlam 2001 Jeff Hardy vs. Rob Van Dam WWF Hardcore Title Match

SummerSlam 2005 Undertaker vs. Randy Orton

Memorable Moments (Free):

SummerSlam 1991 Big Boss Man vs. The Mountie Jailhouse Match

SummerSlam 1992 British Bulldog vs. Bret Hart WWF Intercontinental Title Match

SummerSlam 1991 Bret Hart vs. Mr. Perfect WWF Intercontinental Title Match

SummerSlam 1995 Shawn Michaels vs. Razor Ramon WWF Intercontinental Title Ladder Match

SummerSlam 1998 Steve Austin vs. Undertaker WWF Championship Match

SummerSlam 2007 Triple H vs. King Booker

SummerSlam 1988 Ultimate Warrior vs. Honky Tonk Man WWF Intercontinental Title Match

Other Matches ($1.99):

SummerSlam 1988 British Bulldogs vs. Rougeau Brothers

SummerSlam 2007 John Cena vs. Randy Orton WWE Championship Match

SummerSlam 2004 Eddie Guerrero vs. Kurt Angle

SummerSlam 1991 Bret Hart vs. Mr. Perfect WWF Intercontinental Title Match

SummerSlam 2010 Team WWE vs. The Nexus

SummerSlam 2012 CM Punk vs. John Cena vs. Big Show WWE Championship Triple Threat Match

SummerSlam 1992 Randy Savage vs. Ultimate Warrior WWF Championship Match

SummerSlam 2001 The Rock vs. Booker T WCW Championship

SummerSlam 2009 Rey Mysterio vs. Dolph Ziggler WWE Intercontinental Title Match