The first time I realised how fast computers could be was when I first booted up BeOS on my old AMD single core, probably less than 1Ghz machine.

The thing booted in less than 10 seconds and performed everything so quickly and smoothly - compiling code, loading files, playing media and browsing the web (dial up modem then).

It performed so unbelievably well compared to Windows and even Linux of the day that it made me wonder what the other OSes were doing differently.

Now my 4 core SSD MacBook pro has the same feeling of raw performance, but it took a lot of hardware to get there.