On an Apple Mac OS X computer, turn on sub-pixel rendering this way:
Click the Apple menu, then click System Preferences. Click the Appearance icon. You'll see "Font smoothing style:" in the window. Choose "Medium - Best for Flat Panel" from the dropdown menu.

You should first try turning off all font smoothing for very small text sizes. You can also try altering the font smoothing style from "Medium" to "Light" or "Strong." You may need to play with the settings to get the best results.

For more information on the specific methods of sub-pixel smoothing, use FONT SMOOTHING as the term on Apple's support site at www.info.apple.com.