Excel-based site map generator
A good six or seven years back, I developed an Excel spreadsheet that took a hierarchical data feed of pages (page name, level in the IA, page type) and generated a visual representation for you on the fly. A crop of the visual is shown below.
It used conditional formatting up the ying-yang, with particular complexities around developing the interconnects between the boxes. While there were some macros to re-hash the incoming data, the visuals were all based on conditional formats which were at the time limited to a maximum of three (plus the default format) per cell.
All in all, it was awesome. (If I may say so.) If anyone out there has a use for it, let me know.