I may have this incorrect, so take it with a grain of salt.
Basically, you set your sci slider to zero, and act as a "middle-man" tech broker. You allow the 2 - 4 tech leaders obtain a particular tech, then you buy it off of them. At this point, you immediately sell the tech to the rest of the world -- and, hopefully, in the process come out ahead.
When your timing/position is right, you can attempt to "sling-shot" beyond the tech leaders by self-researching a fairly neglected/little-used tech, to sell to the tech leaders. This has worked to great effect in some of my games.
Have you checked the War Academy?
-V