Technology, and the Internet in particular, have rapidly transformed the means of communication in the 21st century, opening the door to a novel and fertile ground of research. What takes place when bi- or multilingual individuals sit at the keyboard has been the focus of several studies exploring computer-mediated communication (cmc). However, there appears to be a lack of research dealing specifically with Spanish-English language mixing online, a surprising fact given that Spanish is the third language of the Internet and its use has grown 800% in the last decade. The present work analyzes and compares data from three different sources of cmc (e-mail, blogs, and social networks including Facebook and Twitter) among Spanish-English bilinguals in an attempt to further explore the still relatively new field of “electronic code-switching”. The study aims to outline the reasons behind bilingual individuals’ language mixing online, hypothesizing that it will accomplish many of the socio-pragmatic functions traditionally ascribed to oral code-switching along with, perhaps, other uses idiosyncratic of cmc. Furthermore, it intends to emphasize the cultural nature of code-switching, a crucial component that has often been overlooked in the search for grammatical constraints.