Some of my favourite authors are Serre, Mumford, Milnor, Fulton and Neukirch. There names are rather mainstream, I guess. But the most beautiful analysis textbook I ever read must be ["Analysis now"][1], by Gert Pedersen. Alas, the book is not as well known as it should be.


  [1]: https://www.amazon.com/Analysis-Now-Graduate-Texts-Mathematics/dp/0387967885/ref=sr_1_1?ie=UTF8&s=books&qid=1256484405&sr=8-1