I needed to draw organizational charts for an intranet, containing both vertical and horizontal connected, clickable, multi colored siblings. As flexilibity was important, exported Visio drawings were not an option.
If you need to draw this kinds of charts, you can use my code for free.
Please check the instructions and samples page.
If this script misses functionality you need (eg. images within the nodes, multiple parents per node, zooming), please look somewhere else. I don't have time to implement additional functionality at the moment, I'm sorry.
You can download my orgchart.js with this link.
You can download the excanvas script for IE compatibility by Google. If you trust me, you can use the version used by this page.
If you're going to use this code, I appreciate it if you send me a small mail message. My address is: jvloenen (AT) xs4all (DOT) nl.