Keyboard/Mouse on the couch?

I have been doing it for years.  I have a sofa chair with big cushy armrests, so the mouse works wonderfully on those.  The kb is usually on my lap.  Once I moved my rig from my desk to the living room and connected it with my home theater system, I never went back.

My tv is 52", so I did have to experiment with different dpi before settling on a setting I liked best.

Depends on the game.  Skyrim for example was awesome on it.  But some other games were neither more or less of a good experience, just bigger basically. But browsing the internet on it is always better.  Especially when streaming movies and shows.

I tend to watch movies and TV shows on my home entertainment system that interfaces with a Logitech Harmony remote. I have my gaming setup on a desk that sits in front of an ergonomic chair. I'm using the BenQ XL2420T high performance gaming monitor that offers almost no input lag with less than 2ms response time, 12M:1 DCR for an ultra-clear picture, and a 144Hz refresh rate which enables high framerates. It's flicker-free to reduce eye strain after long gaming sessions, and it covers a much wider field of view because I'm sitting closer to it.SKaREO

I've been doing it for awhile. Ever since I moved I haven't had the room to have a computer monitor and a TV. So I'm just using the 42" as a monitor. Its been working rather well for me.

I have my setup like that lol, using a small table. 

Sometimes I have the keyboard on the lap and glide the mouse over the couch fabric when I'm on the Windows desktop. When I'm gaming, I use a TV tray:

I also have a futon in my den. Sometimes I use the desk. Sometimes I lounge on the futon and use a TV tray for mouse n keyboard.

I've done this for years, got myself a EKORNES Stressless chair recently so I've been moving my ass from the couch and into that, comes with a wooden table for my mouse.