Dockable window/Always visible. possible?

[GreyArea]

I'm not sure this is possible, but figured I would get some opinions before I tell the client. I was asked to create a small application using a web front end. They want this app to run in a window that is always visible, kind of like a toolbar. So even if the user is in word, this window would still be visible above the word titlebar.

TIA

[Fang]

Not with a browser. Only installed apps can do that.