Non-local forms of file storage and transfer provide investigatory concerns. Whilst mainstream cloud providers offer a well-established challenge to those involved in criminal enquiries, there are also a host of services offering non-account based ‘anonymous’ online temporary file storage and transfer. From the context of a digital forensic investigation, the practitioner examining a suspect device must detect when such services have been utilised by a user, as offending files may not be resident on local storage media. In addition, identifying the use of a service may also expose networks of illegal file distribution, supporting wider investigations into criminal activity. This work examines 16 anonymous file transfer services and identifies and interprets the digital traces left behind on a device following their use to support law enforcement investigations.