Tempest is Clears bandwidth offering for Small Offices in New Zealand. You get One IP address, and you pay for how much bandwidth you want. The first offering is 256kbit upstream/downstream and is price equivilent to JetStart. They will go up to 2mbit both ways. However it's only available to Businesses.
Clear will figure out the best way to deliver you Tempest depending on your location, for instance if you are in the CBD, they will probably use ADSL, where if you aren't you'll probably get wireless InterNet.