One addendum -- it looks as if it's a hardware issue after all. Wiped the drive, reloaded critical applications, and more !@#$%! kernel panics. My tech support-ish husband thinks that's a sign it's a hardware problem, and I'll have to ship my Mac back to the mothership for repair.
I am still sketching, and if the weather holds tomorrow will get some extra memory for the camera so I can wander. But sharing is painfully limited to words-and-hyperlinks only for now, since I preprocess images in Photoshop to get them fit to post.
Will post another sick Mac update when I know more...
Meanwhile, I'll see you in your comments-kitchens, and when the random poem hatches.