Using this app: http://infinite-labs.net/afloat/
It's for mac, there's gotta be a windows equivalent but it just creates an overlay of whatever window you want and you can click right through it. The transparency is adjustable as well.
I've been doing that for a long time. Maybe not that small, but I know how you could get really close.
Make a new window and bring up the netflix player page. Turn off the all the bars (address, bookmarks, status) and make the window as small as silverlight will allow. If that's not small enough you can use ctrl-minus (-) (or cmd-minus on mac) and make the player even smaller and further shrink the window. See:
I'm on a mac, but this should work on most browsers I can think of. Plus, I have an app called Afloat that can make pretty much any window I want system wide always stay on top of other windows. Perfect for netflix.
Hope this helps.
I always just use aloat to resize windows via a keystroke + drag mouse from anywhere. I can't be bothered even bringing my mouse to the edges, much less a corner =P
I also use it to move a window without having to bring my mouse to the titlebar - once you get used to it you can't go back! I have other programs that do the same thing for Win+Linux too.
Theres a plugin for osx that lets you set some windows to be on top of other window layers, and also allows you to set them to various amounts of transparency. It's called Afloat.
I don't think there's a way to set an application to be on top and to avoid keyclicks at the same time. I'd suggest watching Netflix in a window underneath a mostly-transparent chat window application that does work with the Afloat plugin.
Not every program works with afloat though - most notably for me it's Firefox that doesn't, so I do most of my video watching in Safari in a on-top window while I'm websurfing in Firefox and chatting.
It might be helpful to know why you're trying to achieve this. Do you want to constantly see a part of your wallpaper? Or do you want Quicktime or whatever player you're using to be the frontmost window all the time? Or something else entirely?
Because depending on what your goal is someone might know a solution which isn't exactly what you're describing. E.g. if you want a window to be the frontmost all the time you could use Afloat. It doesn't reserve a specific screen area but keeps other windows from being drawn above the one you want to be the frontmost.
So again: a little more info would be helpful in case someone knows a solution to your problem you haven't thought of yet.
the closest thing i can think of is only full screen (f11).
for 'set on top of window' you can try afloat
source http://superuser.com/questions/182016/keep-a-window-always-on-top-in-mac-os-x
You can use Alfoat to keep Cocoa app windows on top (and some other stuff). Another option is to pipe top through GeekTool which can be set to run on top of other windows.