Does the D80 not have a sensor cleaner built-in? I thought all the recent releases had a sensor shaker these days. Or have you got some stubborn dirt, Chris?
Like you, I got frustrated with dirt on the sensor, a bit fanatical in fact, as I have bought extra bodies over the last year or so and don't need to change lenses nearly as often now. My last remaining non-self-cleaning body, a 20D, essentially never has the 10-22 unplugged from it, and the 40Ds I am most likely to need different lenses on largely look after themselves.
"Ruminations". That's a nice word for it. I'd have called it a "dummy-spit" myself, but them I'm not really a gentleman.
Hyperfocal distance is actually pretty simple if it's explained right, and so long as you don't want to go into too much detail, but I'll have a crack at that in another post.