Found via Penny Arcade: http://posterazor.sourceforge.net/index.php?page=about&lang=english (http://posterazor.sourceforge.net/index.php?page=about&lang=english). This is a really neat way to print images larger than a single sheet of paper on multiple sheets of paper, then combine these multiple sheets into a single large poster without any white between pictures.
Seems quite useful if you're printing off large D&D battlemaps or large Happy Birthday banners...