Seeing as how everyone is probably going to agree with me I will list what I like

Studio Bones
Studio Bee-Train
Gundam

My collection is pretty much that. I usually like what Bones and Bee-Train churn out(although Eureka 7 has not caputured my interest at all and Wolf's Rain was...yeah). I am sucker for Gundam. There are others here and there like Bebop or Inuyasha that have captured my interest but I stick with what I know for the most part and don't stray from it.

The best ones out of this are hack//sign(bee-train) and FMA(bones).