Just a caution for those looking at using the PPS to sync remote data things, not all GPS modules or GPS shields provide PPS output so look at the docs carefully. I am using Maestro GPS 1035 and 2035 modules about $20 and $18 from Mouser they work great and the price can't be beat. The 1035 and 2035 are surface mount units and need to either go on a breakout board of a shield to use them with Arduinos, they skillet reflow very nicely but you will need to fab a board first.
wade