Paul,
Are you talking solid state or a real hard drive? I haven't seen 100GB
solid state thumb drives, but I haven't been looking
Below are some other things you might be interested in.....

-----Here is an extension to Bob W's rsync suggestion.--------

If  you try 'rsync', which is what I use for backups, be very careful
with '--delete'. If you do it backwards your screwed. Experiment
without it, then add it when your happy that the command is doing what
you intend.

'rsync' will work between machines over a network. I prefer to use it
over 'ssh'.  It encrypts the traffic and you do not have to start a
'rsync' service on the target machine.

'rsync    -av   -e  "ssh -l remote_user_name"     --delete
localpath     remote_machine_name:/path'
This will require a password for the remote_user_name.

----And even more: use rsync over ssh without a password--------

To use it with no password in a script, create a set of ssh keys.
   'ssh-keygen -b 2048 -t rsa'       //hit enter at the password prompt twice.
This will create a private/public pair of keys. '~/.ssh/id_rsa' and
'~/.ssh/id_rsa.pub'.
Copy the id_rsa.pub to the remote machine, then on the remote machine
append it to the remote users authorized_keys file:
   'cat id_rsa.pub >>/home/blake/.ssh/authorized_keys'.
Set the permissions:
   'chmod 600 /home/blake/.ssh/authorized_keys'
'blake' being an example remote user.
Then when you
   'ssh blake@remotemachine'
it will use the keys to authenticate you.

   If you put a pass phrase on the private key, you will have to type
it on every use of the key, which is a good idea if you use the key
interactively. I keep a pass phrase protected copy on my USB drive, so
I can use it on other machines. You have to trust the 'other machine'
somewhat, though no more than if you used a username/password.
   SSH will not use the key if the .ssh directory is readable by
other users. The easiest way to create the .ssh directory with the
right permissions is to type 'ssh localhost' and then ctrl-c out of
it.

I'll be happy to help anyone trouble shoot ssh problems. There can be many.

I keep Windows versions of ssh and scp on my usb key so I can use
others machines and copy things to home machine.
Windows single file 'ssh' a 'scp' executables: 'putty.exe' and 'pscp.exe' at:
"http://www.chiark.greenend.org.uk/~sgtatham/putty/download.html"

----secure password/account management-----

For account and password management I use KeePass. Which uses good
encryption to store username and passwords. I keep all my
bank/creditcard/financial info in it too.
"http://keepass.info/download.html'
For Windows get the portable package, it does not install on the
machine but runs from USB drive.
I have put Linux and Windows version on the USB drive so I can use it
either way. They both see the same data.
Linux may have keepassx installed or available to install as an network update.

Blake

I am talking real hard drives.USB version are up to 500 Gig

Paul Lamar