Lu Zuckrman,
Have you a good link to those C-130 recovery shenanigans? It sounds very clever...I had no idea.
I'm a final yeat physics and space technology student and we've just had the pleasure of some questions regarding this tether idea. In February '96 a metal sphere on the end of a 20km tether was lowered from Columbia. The voltage induced by the tether cutting the Earth's magnetic field can drive a current by attracting electrons from the ionosphere on to the sphere at one end of the sphere while elctrons are ejected from the Shuttle at the other end by an electron gun (like in a TV).
When you tether two orbiting bodies (e.g. the Shuttle and a satellite), their centre of gravity lies somewhere between them and the result is that both are travelling at speeds which differ from their expected circular orbital speeds at their respective altitudes. This leads to the Shuttle experiencing a small amount of 'gravity'.
Mr. A. C. Clarke is truly a visionary...he was writing about space elevators and geostationary orbits moe than half a century ago...crikey
Mav