If you are using an Android handset like the Samsung Galaxy S i9000 and bored of seeing the default system fonts on your mobile phone, then here is a tutorial which helps you to change the fonts. To implement this tutorial on your android phones, you need to root the device. To do this, you need to follow the steps mentioned here which contains three scripts that need to be run (using GScript or GScript Lite which is available free in the Market).
Your new fonts need to be copied to your SD card along with the three scripts. You can follow the detailed steps mentioned here.