I might as well game directly on that machine.
I have a family and so don't always have access to my gaming PCs (I have 2). In fact I frequently don't have access to either of my PCs.
Gaming PC number 1 is a regular desktop in my bedroom and is often pinched by my daughter to watch Netflix.
Gaming PC number 2 is a HTPC in my living room connected to my plasma - and the plasma is often used by my wife to watch TV.
I can use PC number 2 to stream games onto my (core 2 duo / Intel GMA 4500) laptop when the TV is in use.
I can use either PC to stream games onto my laptop so I can play in bed.