
pdfposter
This requires the installation of Python and pyPDF. Out of the gate, the script does not provide for image overlap, however there is a patch that does fix this. The patch requires replacing 5-6 lines in 3 files and adding 2-3 new ones, its very easy. The patch is here: http://pdfposter.origo.ethz.ch/node/39 . Also note this program requires the installation of Python 2.5. If you just have Python 2.4, you will get errors. This solution is ripe for an open source web front end, which would then allow a popping up of all kinds of new free services on the Web to make posters.