You can still sit back in your chair, you just need a mouse like this one.
http://www.pcmag.com/article2/0,2817,2412536,00.asp
Or this one
http://www.pcmag.com/article2/0,2817,2411473,00.asp
They gives you all the options that you see on modern day cellphones. Two finger scrolling, pinch to...