This essay attempts to make color “run” in various ways, to make it run fast (color-fast) between ontological and logical categories. Three ways of becoming-blue, three steps into writing/painting via the color blue are traced: blue Joyce, blue Gass, blue Klein. Three “countries” of the blue, opening onto labile regimes of in-betweenness: between two roots of the verb “to be” (esse/*blu, both active in Joyce’s Ulysses), or between proper and common nouns (from William Gass to Klein’s gas or Joyce’s Gas from a Burner).