When I've read this news, I've immediatly thought about Enigma@home

http://www.networkworld.com/community/blog/fbi-wants-public-help-solving-encrypted-notes

If you have free time and if some people are willing to help, may be you can give a hand?

Sounds like a good idea to me. Unfortunately, it isn't as simple as saying 'lets decrypt this by brute force'. Before we can go down the brute force route, we need to have more of an idea of how this was encrypted in the first place.

It can't be too difficult because it looks as if it has been done by hand. If the FBI have run out of standard approaches on this, it suggests something like a one time pad or its equivalent (maybe a book from a shelf in the house) that was used to encrypt the message. This would make it exceedingly difficult as we'd need some idea of which book, etc.

Don't underestimate criminals and their coding capabilities. I watched a National Geographic special on the Arian Brotherhood recently. Their top commanders control the organisation from within bars using encoded messages that are usually handwritten.

The FBI helped local investigators crack some of the codded messages, and found that they were using a form of the Enigma code from WW2.