The April, 1996 issue of Scientific American featured an article called The New Backyard Seismology, which describes how the amateur scientist can make their own seismograph. This personal seismograph is now an inexpensive undertaking due to the availability of a new product.
Using a new breakthrough technology, amateur can now, for about $100, easily build seismographs that are robust and that approach professional quality. The breakthrough is a remarkable micromachined accelerometer on a silicon chip.