I worked with a DirectTV satellite link while testing my company's acceleration device.
Satellite uses TCP tricks to optimize the connection and reduce the effect of the excessive latency. My observed latency was from 1.4 to 2.0 seconds. What that means is if you want to play games online, it will never work. But if you want to download files and surf, it is ok. Once you get a file downloading, it could reach 400kbps, and that is due to the tcp spoofing and transparent proxy tricks they do to minimize the need for TCP acknowledgements to traverse the satellite.
The problem is that with 1.5 seconds of latency, anything you do like click on a link or send an IM message will have a 1.5 second delay before anything happens, and that can be frustrating.
In contrast, dial-up is .15 to .3 second latency, so it seems to respond faster but the total download speeds will be one tenth of peak satellite speeds.
If you do a lot of surfing, try Earthlink or Netzero premium dial up with their accelerator technology. I know how that stuff works under the covers and it is pretty impressive (it's not just client side caching, it's more complex than that).
If you do a lot of downloads, check into satellite. However, some satellite terms of use contracts will state that they have the right to throttle download speeds if they detect you are doing a lot of downloads and sucking up limited satellite bandwidth during peak hours.
Hope this helps.
--kurt