I am Intrigued by this idea, it goes beyond the basic idea of travelling through time, this is changing future time to your advantage.

If you were to travel back in time from today with a computer, say a P3 1 gigahertz PC(bet this goes out of date fast), to 1975, give it to Intel (who are currently messing around with prototype 8086 chips) what would happen? 

They get future technology years ahead of its time and it accelerates the scientific gains for the time, now travel forward in time, and your original timeframe (different timeline?) have technologies far in advance of when you left.