This study theorizes connections between semiotic resources and mobility in public displays of language with reference to data from Brownsville, Texas and Betultujuh, Central Java. From an ethnographic perspective, the paper explores the relation of public signage to the mobility of human beings and the mobility of texts in space and time. The semiotic landscape of Brownsville reflects a stratified sociolinguistic space shaped by a history of contact between English and Spanish and the continuing movement of people, goods, and texts across the U.S.-Mexico border. In Betultujuh, by contrast, a semiotic landscape characterized by indeterminacy, amid the influence of national language ideologies and globalizing English, shows evidence of a cultural shift mediated by the circulation of material artifacts and features of language. Based on these analyses, it is argued that porous borders between languages are tied to the mobility of people, texts, and things in a globalizing world.