No I don't and nobody else does either. With my Revit focus, there are no applications that have IFC (Industry Foundation Classes) as their native tongue, sole language. I also can't help but think of Isaac Asimov's Foundation Series of sci-fi novels too.
For me trying to use IFC is like this scenario:
A room full of students in a Spanish class, none of whom speak Spanish but hope to learn. We study hard for a few weeks and then try to have a conversation. Lot's of talking, not much understanding and certainly not very effective. Even after more study we find that the Spanish we are speaking has changed because there is a new version. Now we need to study and review that version...repeat...
IFC as neutral format to help us share digital building information is a noble idea, just not sure it, or all the companies that have to conform to it, will ever live up to it.
[Edit/amended May 21, 2010] Guy wrote a post on his blog regarding this subject.