In this paper, we address the task of affect recognition from text messaging. In order to sense and interpret emotional information expressed through written language, rule-based affect analysis system employing natural language processing techniques was created. Since the purpose of our work is to improve social interactivity and affective expressiveness of computer-mediated communication, we decided to tailor the system to handle style and specifics of online conversations. Proposed algorithm for affect analysis covers symbolic cue processing, detection and transformation of abbreviations, sentence parsing, and word/phrase/sentence-level analyses. To realize visual reflection of textual affective information, we have designed an avatar displaying emotions, social behaviour, and natural idle movements.