A better workflow for screen real estate than spaces?
Really, you can't beat two physical 1080 monitors and an extra, smaller (~1024x768) one (touchscreen a plus). This works best for headless machines, or machines with an integrated 1080 display. Here are example workflows for different scenarios (Big1=1080 main, Big2=1080 extra, Small1=small extra):

Coder:
Big1: The piece of code you're actively working on. Big2: The list of related files (like in XCode), and the interface design. Small1: Where the app's windows(s) go when you test it, unless it's big. Or music controls.

Web Developer
Big1: Code. Big2: Browser preview. Small1: FTP client or ebooks or list of files or editor utility panels.

Photo Editing/Design
Big1: Editing window (Ps controls, image, etc). Big2: List of photos w/ previews.
Big 3: Original image or music controls or editor panels.

Student (the one I spend the most time in)
Big1: Paper/essay on the left and outline on the right. Big2: Research websites, ebooks, works cited, etc (two open simultaneously works well). Small1: Music controls or assignment sheet/project requirements.