Copying and pasting text between applications without style
O/S X does have a "universal" key combination to paste without any style, it's SHIFT-COMMAND-OPTION-V

Unfortunately Microsoft uses their own text engine rather than the Mac's built-in one so that does not work there. The only options I have found for word is to create a Macro to paste plain text. You could download one of this but the one's I found were for the PC version and I never got them to work in the Mac version.

But I just find it easier to paste it into a plain text editor (I use Bbedit or TextWrangler, the free version.) Then copy and paste that into my word document. Annoying but it works for me.

I believe there are a number of clipboard utilities that will do what you ask. A quick visit to macupdate.com should help with that.