http://ernst.mb.jhu.edu/
"Why Ernst? If you want to quickly test a neuronal network model and don't want to spend much time in writting a simulator and learning a new computer language. If your neuronal network is complicated and large, which cannot be simulated in one machine and you want to distribute it in multiple machines If you want your neuronal model to be realistic in terms of neuronal dynamics and accurate in the spike timing If you want something run out of box without any worries of compiling and installation If you want your simulator extendible to fit your need Then ERNST is your choice."