completely clean and tidy (about a room, a house, etc)
spic and span
slightly ill
under the weather
something that seems to be bad or unlucky at first, but which you later realize is good or lucky
a blessing in disguise
with the usual outside parts on the inside
inside out
as fit as a fiddle
to be very healthy and strong
in a position with the top at the bottom and the bottom at the top
upside down