Without doubt, the ubiquitous Blue Sun Corporation is the richest and most politically connected corporation in the system. Blue Sun (Chinese: 蓝日 lánrì) is on every planet, in every home - rich and not so rich alike. For all its fame, it is one of the most shadowy institutions in the 'Verse.
The Blue Sun logo is everywhere: on T-shirts, billboards, posters, food cans, etc. The logo has become so much a part of daily life that people don't even notice it anymore. Blue Sun products are considered essential to a person - like water and breathing. Just look for the Blue Sun label. It's never difficult to find. The company doesn't operate retail outlets, but every shop stocks its products. While not the best on the market, Blue Sun products are the most reliable. If you buy Blue Sun, you always know what you're going to get. There are never any surprises - good, bad, or otherwise.
Blue Sun produces a lot of different things, but the company concentrates mainly on the basics of life. Folk will always need food and drink, and Blue Sun is there to sell it. They hold the monopoly on packaged foodstuffs, and their products have become essential to people on the newly terraformed worlds. Many new settlers wouldn't have made it through their first year without Blue Sun packaged food.
Blue Sun didn't get into business out of love for their fellow man. They started the company to make a profit, and no one begrudged them that. But then, as the company grew bigger and bigger, and became more and more powerful, greed and corruption took over. Profit was the only thing those running Blue Sun could think about. They set out to make more and more money by extending their power as far as they could manage.
It's an open secret that Blue Sun engages in deadly corporate espionage and then calls in favors from powerful government officials to help cover their tracks. Its subsidiaries and shell corporations have branched out far from food and service industries, going into computer systems, communication technology, and even spaceship design, along with the biotech industry - even going so far (some whisper) as to conduct experiments involving living humans. Only top executives have a good grasp on what the 'big picture' is when it comes to this mega-corporation. Its research and development division is a mysterious place guarded by security equal to top secret Union of Allied Planets military projects.
- Firefly – "Serenity"
- In the pilot episode, the Cry baby #6 was a radio transmitter taped to a Blue Sun coffee can. Blue sun is speculated to be a ubiquitous corporation creating foodstuffs, technology, and other household items.
- Firefly – "Bushwhacked"
- Janyne wears a Blue Sun shirt in Bushwhacked, this is the shirt that River slashes in Ariel.
- Firefly – "Shindig"
- Firefly – "Ariel"
- In the episode Ariel, River slashes Jayne with a knife across the the Blue Sun logo on his t-shirt. As before, it is speculated, that River was lashing out against Blue Sun as her past tormentors not Jayne himself.
- When Simon boots up the holo-imager a spinning logo appears before the machine begins to show Rivers internal organs. If you look closely at the center of the spinning element of the hologram you can clearly see Blue Sun's logo (it appears backwards because it is presented in a manner that would appear correct to the operator of the imager, Simon. 
- Firefly – "The Message"
- Serenity movie
Behind the scenes
Joss Whedon once described Blue Sun as a combination of Microsoft and Coca-Cola.
Blue sun is featured on the Webcomic Ctrl-Alt Delete http://www.cad-comic.com/comic/of-champions