This paper presents ongoing work on the topic of physical modelling and force-feedback interaction. Specifically, it proposes a frame- work for rapidly prototyping virtual objects and scenes by means of mass-interaction models, and coupling the user and these objects via an affordable multi-DoF haptic device. The modelled objects can be computed at the rate of the haptic loop, but can also operate at a higher audio-rate, producing sound. The open-source design and overall simplicity of the proposed system makes it an interesting solution for introducing both physical simulations and force-feedback interaction, and also for applications in artistic creation. This first implementation prefigures current work conducted on the develop- ment of modular open-source mass-interaction physics tools for the design of haptic and multisensory applications.