Hector is a fast, multi-purpose simulator for the path of particles into beamlines.
It is build to be adaptative to any beamline and is already used by people from CMS (as a part of the official software) and ATLAS at the LHC and STAR at RHIC.
It is written in C++ and uses the ROOT framework to provide nice tools for analysis.
Results were cross-checked versus MAD-X, the official software used by the LHC machine group. It already allowed to obtain many estimations in terms of acceptance and resolutions of very forward detectors, as well as the effect of beamline misalignements and other related important topics related to forward detectors.
In collaboration with Xavier Rouby (Freiburg, D).