Tools
Free Tools for Excel Charting

Tiny Graphs Tool
Tinygraphs is a free open source add-in for MS Excel, which creates Microcharts.

Buenavista Charts Tool
Buenavista charts is a little plugin to display tiny graphs in excel.

Excel to JPEG Converter
Free Excel/Xls to Image Jpg/Jpeg Bmp Tiff Png Converter can create image format from documents including excel(.xls, .xlsm, xlsx).It can convert one file format to image format once.