Basically, in Europe and Australia, most ISPs get in 3-10 times as much data as they push out. Your outbound data flows over your terrestrial pipe, and so does some of your inbound data. And you need a router that can receive an 8 Mbps data stream, which isn't cheap. There are various ways of encoding those streams, ranging from Frame Relay to IP tunneling. But that's the basic idea.
Geosynchronous satellites are way out there.
Tens of thousands of miles out. It takes a long time, relatively speaking, to get data out to them and back. Then, to send it back over fiber or copper takes 100-150ms. The total is 400ms or so on average. It turns out that 400ms as a total round-trip time is a lot better for TCP utilization and perceived throughput than 600ms.