This thread is in the aim of finding a solution to all these common problems: if you are the owner of a bricked hermes, please post your comments here instead of opening a new thread.
There seems to be 3 types of bricked (or dead) hermes devices:
We made a wiki page long time ago whith the solutions that have worked for some people to fix bricks, unfotunately these solutions do not work for everyone, some devices are more bricked than others
Type 1 bricks: Corrupted radio area: No GSM, No CID, no IMEI
Usual reason for that is flashing whent wrong when RUU was flashing the radio stack (GSM.nb). Other reason can be that you flashed radio from another device (universal unlocker run on hermes, for example).
Within the type 1 bricks, there seem to be two variants:
Type 1a:devices which can boot windows mobile but can't use the phone functions.
Type 1b: devices which can't boot windows mobile and are stuck while booting, see also type 2 bricks below.
Type 2 bricks: Stuck in boot process
Usual reason for that is that flashing went wrong when the RUU was flashing any rom part different than IPL and SPL. Symptoms can vary depending on which is the ROM part affected. The most common is OS because it is the bigger part. Radio is the second most common.
Type 2a: When the phone boots, it goes directly to bootloader mode (tri-color screen)
Type 2b: When the phone boots, it stays in subslpash screen (htc or operator logo)
Type 2c: When the phone boots, it doesn't pass the windows mobile logo
Hybrid Bricks: combinations of both type 1 and type 2 bricks
These usually have a corrupted radio and are stuck in bootloader, unfortunately these are very common too, and the most dificult to repair.
First thing you have to do is visit this wiki page and follow the process explained: Common upgrade problems
If you can't repair your brick after following the process, please provide a USB monitor capture in ANSI text format (this is explained on the wiki page too) as this is the only thing that can give us a real idea on what your exact problem is. Please don't come crying and say "help me" because we can't help you if you don't provide useful information, you are in front of a big problem and you will have to loose some hours reading and experimenting before repairing your brick. If you are not willing to loose some hours reading, go and send the device to the service centre for a repair as it is the only valid solution most of the times.
Hopefully after research of everyone in this thread we can find new solutions for some of the bricks
EDIT: Please use axiom's comment below as a template for your comment and attach USB monitor capture: If your bootloader is 1.04 attach capture when trying to flash an extracted radio ROM and when trying to flash a shipped rom update. If your bootloader is 1.06 or 1.09 only attach the usb monitor capture of the shipped update.
After more than 3 months since this thread started and more than 660 comments, we have now solutions for some bricks, so I compiled the most common on this unbricking guide: