Pipes is a desktop system which analyzes an AutoCad(TM) drawing of a sprinkler system, checks for flaws and after these are eliminated, adds the size/diameter labels to the drawing. Tutorial: http://users.norwoodlight.com/janh/wink/autopipes-entry.htm
SVG export script for powerpoint. You create a diagram using powerpoint's shapes, text boxes, drawing tools, etc. Then you run export_to_svg (a macro) and bingo you have an SVG fragment that you can view in your favourite browser.