I will ad one name to your list of two -it is ACN .
For more, check the source

If I am not mistaken, Usana Health Sciences has been #1 for three years now.

Dilyan has it Dead on. ACN is an incredible company. I have personally met the co-founders of ACN as well as many leaders in this organization. The integrity of the company is outstanding. They have a vision that is very unique. They've helped a lot of people from various different back grounds make something out of their lives. They also support a lot of different charities across the nation. They help a lot of non-profit organizations in their funding to keep their programs going. They also have really good services that people use every day. They have saved a lot of people money on their telecommunications services.

I think is the quickest growing one acording to alexa.
Its a social network that pays users.