Every once in a while I get a hit from someone at Microsoft looking for Visio for the Macintosh related material. They typically land on something I wrote back in 2004 where I mention we once had Visio running natively on the Macintosh. It has a nice splash screen created by Chris Roth, but unfortunately I don't have a screen shot of the actual product. It really did exist, it just never saw the light of day. We also had it running natively on a DEC Alpha and on PowerPC versions of NT, but those both died on the vine as well.
I'd still love to see Visio running on a Mac. If Microsoft ever goes about doing that I'd love to work on it, hint, hint.
They don't need me to make that happen of course, but it would be an awesome application to have on the Mac.