Finale Notepad - To play/read Finale charts in your browser.
Sibelius Scorch - Same as above for Sibelius charts.
MuseScore - Free music composition/arranging/transcribing software.
CutePDF - A great free program for printing your Finale/Sibelius/MuseScore charts directly to PDF (highly recommended!)
PDF-2-JPG - A great online converter for turning PDF files in JPGs.
PDFCombine - Combine your seperate PDFs into a single document, very handy for condensing large scores and big band charts.