What kind of options are there for very high bandwidth long distance data links?
We use Microhard Systems 1.5 Mbps radios that send data over 100km.
They run at 900Mhz www.microhardcorp.com

They make 54Mbps broadband wireless gear too, quoted range is 16km.

We've used their 900Mhz gear for years, and it's only gotten better, from 1200bps to 1.5Mbps.
Works great in cluttered environments (urban or forest)