In 2002, SkyWest Airlines observed its 30th anniversary with this specially painted CRJ2. SkyWest was the first US airline to operate the CRJ, in 1994. They now have some 140 of them, flying for Delta, Midwest, and United. Here at LAX, SkyWest flies as United Express, as seen here, as well as Delta Connection, as seen below.
This CRJ9 is painted for SkyWest's 35th anniversary. That same year (2007) marked 30 years of SkyWest service at LAX. With 140 departures a day (United Express and Delta Connection combined), I believe SkyWest has more flights at LAX than any other carrier. Southwest is probably next, with 119 departures per day.
Trans-Canada Air Lines was started in 1937, and became Canada's flag air carrier. Canada being a bilingual country, the airline was known as "TCA" in English, and "Air Canada" in French. An act of Parliament changed the company's name to Air Canada in 1965. This anniversary livery appears on an A319.
'The Party Plane' flies for Horizon Air, whose 25th anniversary was in 2006. Horizon has over three dozen of these Dash 8's, which are also known as Q400's.
This one was cheating a little, as it's not an airline anniversary, but instead Disneyland's 50th anniversary being commemorated. Known as 'Magic of Disneyland', this Alaska Airlines B737-400 is hard to photograph.
'Starliner 75' is Alaska's 75th anniversary aircraft, and features their original paint scheme. This is a B737-800.