ook for beyond a normal preflight when you're about to
go on a long trip? For example, if you were flying from the west
coast to Oshkosh you wouldn't want to be within 10 hours of an oil
change or a 50/100-hour inspection.

My pre-flight inspections are exactly the same, whether it's a 10 minute
or
10 hour flight. Stuff that breaks ain't watching the clock.
--

Some fairly obvious things -- you'll want to be sure your flight bag has the
current charts, for example. You'll want to checkl notams and the like. You
may want to make special note of frequencies -- atc, tower, just in case you
miss a call and don't want to take the time to look them up or call flight
service.

If it's out of the country, suitable documents for crossing national
boundaries.

I like to take travel guides, too, in case there's tiome to visit something I
might have otherwise forgotten about.

If it's a long legged trip with some passengers who aren't used to being
without a rest room, some one gallon zip lock bags do well for (male) urine.

And oh yeah, a credit card or two!!

Btw, those wash and dry packets are pretty handy too, for getting rid of av gas
smell on your hands when you check the tanks anytime.