The biggest barrier to effectively using your Mac (or your iPhone) isn't processor speed or software compatibility -- it's poor typing speed. Who knew back at the invention of the manual typewriter that the QWERTY keyboard layout (alleged to have been designed to slow down typists and avoid jams) would still be our primary data interface more than a century later? Yes, we've got some other options now, but short of upgrading your RAM the best way to speed up your work is to simply learn to type.
To enhance that finger business, check out TypingWeb, which now offers a Safari-compatible (both for desktop and iPhone, as we originally noted here) and free set of typing drills. Using the service on my iPod touch, I discovered that my Blackberry-style two thumb technique was actually slowing me down compared to an index-finger approach that leveraged the word completion feature more effectively -- who knew?
For a full-scale Mac typing tutor, the classic (not Classic -- it runs in OS X now) choice is Mavis Beacon Teaches Typing, available on a cross-platform CD.