I have had my HTC Desire (purchased from Expert Infotech here in NZ) for some months now, and a few days ago I decided to root the unit in order to flash some custom ROM's to it.

WARNING: you flash any ROM code to your device at your sole responsibility. I will take ZERO blame for any mistakes or foul ups.

Here are a few notes on my experiences...

I used the Unrevoked program to do the rooting, following instructions found at http://myhtcdesire.com/
I suggest those interested in doing this read the guides on there for the details.

Basically, you first ROOT the phone (hack it to gain full access), replace some of the boot code (BIOS on a PC) with code ("clockworkmod") that facilitates installing more code (the new ROM), then loading that code off the SD card in your phone.

I went to XDA developers web site, HTC Desire section, and read various threads regarding the ROMS available, and proceedures needed. One early stumbling block I ran into was most of the guides assume the OLD method for rooting the device - unrevoked is new - so I had to figure out where that put me.

With the unrevoked system, really all you are left to do is put the ROM zip file on your device, boot into the bootloader (hold volume down in while you power on the phone), and follow the menus. The same is done for flashing a new radio (you will have to if coming from android 2.1).

I tried several roms, but have been most impressed by "pays desire froyo sense v1.3" rom. It seems very stable and has additional features and pre-installed apps (nothing to big).

Comments are welcome. What were your experiences?