On the original question (which I seem to have missed) there's a lengthy list of candidates.
If it counts as an aircraft, a Space Shuttle flight would be WAY in front for me. If not, perhaps a Virgin Galactic 'space' flight .... or a passing UFO. Failing that, probably the vomit Comet.
If we're restricting it to conventional aircraft ..... that'd take a LOT of thinking about to decide, because we're spoilt for excellent choices.