Temporary nand unlock (until you reboot phone)

[BoNg420]

Disclaimer:
Doing this will have no adverse effects. What you do after could cause problems. Flashing different things to your phone could potentially cause problems, editing/deleting of systems files will not cause you any issues, just make sure you do nandroid backups beforehand, just in case you get a boot loop, you can go back and restore your nandroid. Other then that if you are a noob, don't do anything that you don't understand.

Its actually quite simple.

You even already have the tool(s).

Simply launch unrevoked tool.
After it reboots to bootloader and does it thing you will see the screen flash to the white HTC Incredible screen pops up.
Unplug your USB now before it loads past the bootanimation, make sure you do it before your phone completely boots and while the unrevoked program still says Waiting for reboot.
Once you boot you now have unlocked NAND.
Its a pain yes, but it only takes what 30seconds-minute tops to run the tool and reboot.

It was actually quite obvious if you realize what their tool is doing it unlocks the nand so it can write recovery to it. So if you unplug your USB cable before the tool reboots your phone again, you still have an unlocked nand.

Can simply be tested by running the app AD Free. Then updating your hosts. If it it successfully updates your hosts file, then you are able to write to /system/