First of all I take no credit in Z4Root, I have just made the instructions. Do this on your phone, not on your computer!

You Will Need:
Android Device (AT&T doesn't work this method)
Z4Root.APK [ Register or Signin to view external links. ]

Phones that dont work
Desire (requires nand unlock)
Desire HD (requires nand unlock)
Magic (unknown)
Evo (requires nand unlock)
G2 (requires nand unlock)
Archos 70 (unknown)
myTouch 3G (unknown)
Wildfire
Droid Incredible

Steps:
1. First go to settings > Applications > Check "Unknown sources"

2. Go to the Market and Download "Download All Files" and "Quick App Install".

3. Download the Z4Root.APK

4. Open "Quick App Install" and find the Z4Root.APK and Click Install.

5. Open Z4Root and choose permanent root, let it do everything and reboot and you have a rooted android phone.

If you don't care for the root just go back to Z4Root and there is an unroot option.