Recommended small office printer and/or scanner?

I am looking for a printer and scanner for a 2-person office. No preference between an all-in-one unit or separate machines, I can go either way.

Looking for testimonials. What specific models have you used? Would you buy the same one again?

Basic needs
—Economical, not an ink/toner hog
—Mac and Windows compatibility
—Sheet-fed scanning, at least 10 documents at a time

Bonus points:
—Network sharing
—Duplex (two-sided) scanning
—Duplex (two-sided) printing