Is that
http://qcn.stanford.edu/sensor/ or http://qcn.emsc-csem.org/sensor/ or http://www.ras.unam.mx/sensor/ ?
Here's the needed hardware:
From this webpage: How to become a volunteer 'quake catcher'
You can also do it on your RaspberryPi: http://qcn.stanford.edu/sensor/forum_thread.php?id=880