I’ve just installed a really useful tool to help me deal with my array of monitors called Ultramon. The big benefit is: having a taskbar for each monitor, that only displays the applications open on that monitor. Having four screens worth of apps open is one thing, but switching between them in the taskbar was getting to be a pain.
K! - the blog of Karl Bunyan 
Yeah, I’ve been using Ultramon for a few years, it’s pretty sweet. (I also like that you can have 1 desktop background per monitor, although that’s hardly groundbreaking functionality.)