Hey
I think i know about as much on this subject as you...
However, some points. If it's impossible for someone off this board to access these shares, it's not a security risk, unless someone can somehow make your network think theyre a trusted system, which isn't too hard i don't *think*
As for password cracking, what yo uare doing is a basic password crack, using a dictionary...as you can see it's not very effective, i read somewhere that it would take 16 billion years to test all possible characters in a 1-8 letter password, with a cracker running at 1million passwords/second. That's a lot! Password crackers aren't what some people make them up to be.
Also, i have no practical experience as yet, but if u can access a share you have read/write access to it, including reformatting the drive.......
So it is a problem.
