About 20 years ago, I was programming for the Hughes radar signal processor, a highly parallel pipelined machine which accounted for much of Hughes success in radar processing. Anyway, I needed to compute e^x for 0 < x < 1. The processor had a multiply, so I used four 256 long tables of e^x for each possible 8-bit values in the 4 blocks in the 32-bit word, multiplied them to get the final value. It was about 5 times as fast as the previous best e^x routine. That machine was fun! It is obsolete now, but for many years is could process radar signals faster that processors that were nominally many times faster.