Mac users interested in Nup maker by mckenzie alexander for osx generally download:
PDFnUP is a high performance server tool from Traction Software for Windows PC, Unix Aix, Linux, Macintosh OSX, SUN Sparc Solaris, HP-UX
NOTE: This Software does NOT require Acrobat, PDFnUP is designed for server usage.PDFnUP software automates the process of 2up'ing, 4up'ing or 6up'ing a pdf document, so for example with a/b 2up page 1 is on the left and page 2 is on the right.
