(This list effective as of June 2004.)
-1, 2, 3, 4 are for digipeaters and other home stations
-6 is for Operations via Satellite
-7 is for TH-D7 walkie talkies
-8 is for boats, sailboats and ships (maybe 802.11 in the future)
-9 is for Mobiles
-10 is for operation via The internet only
-11 is for APRS touch-tone users (and the occasional Balloons)
-14 is for Truckers
-15 is for HF