This paper discusses biometric borders in Europe, focusing on the Eurodac database and practises of fingerprinting people on the move in Greece as a politicised attempt to control and limit secondary movement as set out in the Dublin Regulation. The paper presents empirical research to explore one way in which migrants in Athens negotiate Eurodac; where alternative imaginaries informed ideas of 'big' and 'small' fingerprints, shaping interactions with the asylum service as well as secondary movement. I use Autonomy of Migration (AoM) theories to depict borders as places of ongoing conflict, subjectivity and transformation and introduce the work of Castoriadis' social imaginaries and the radical imagination to explore migrants' alternative imaginaries. I argue that these occur at points of friction, within the constraints of, and alongside, a dominant socio-technical imaginary driving the proliferation of biometric border controls. I believe this enables a deeper understanding of the autonomy with AoM theories. Here, autonomy is presented as instances of self-creation, spurred on through the radical imagination and shaping moments of uncontrollability, where the subjective dimension of migration informs both meanings of autonomy as well as alternative imaginaries. Ultimately, I argue that these practices seek to disrupt and challenge the dominance of biometrics as a signifier of control, identity and truth.