The Fragment String is a new digital musical instrument designed to reinterpret and reflect upon the sounds of the instruments it is performed in collaboration with. At its core, it samples an input audio signal and allows the performer to replay these samples through a granular resynthesizer. Normally the Fragment String samples an acoustic instrument that accompanies it, but in the absence of this input it will amplify the ambient environment and electronic noise of the input audio path to audible levels and sample these. This ability to leverage both structural, tonal sound and unstructured noise provide the instrument with multiple dimensions of musical expressivity. The relative magnitude of the physical gestures required to manipulate the instrument and control the sound also engage an audience in its performance. This straightforward yet expressive design has lent the Fragment String to a variety of performance techniques and settings. These are explored through case studies in a five year history of Fragment String-based compositions and performances, illustrating the strengths and limitations of these interactions and their sonic output.