This topic has really been overdone, but here's mine:
1. Swissair (simple, professional, but still retains it's red Swiss flag, very traditional)
2. USAirways (professional, personally I think darker colours just look better)
3. British Airways (yes I actually like the new "Union Flag although my favourite was "Scotland")
4. Austrian Airlines (much the same to ex-partner Swissair, retains Austrian flag, used since the airlines beginning in 1957, not austentatious, not extremely colourful, but tasteful)
5. AA (despite being like 30 years old, I still think it's very classy, although they do have a tendency to get dirty, I keep hoping to see the 'Retrojet')
These are among my favourites.
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