routing with grass

[bld at psrc.wa.com]

Does any one know how to do routing with the grass gis package?  I would
like to use the tigerline files, a satallite image, and an address
database to produce a route to visit sites on the map, and to produce an
optimum path for least time to visit (x)number of nodes.
Any one know how to do this with grass?  Don't advise by arcinfo, etc, I
cannot afford it!
TIA
bld at psrc.wa.com