Best encryption device driver for MS-DOS?

[root]

> 
> Being in the consulting business, I often write prototype software for
> clients in Visual Basic as proof-of-concept and also to make sure I
> understand the client's needs before I accept a project.  On occasion,
> I have to leave my laptop unattended on someone's desk while I go into
> meetings with senior management and try to convince them that I know what
> I'm talking about and that I'm worth whatever (exorbitant to them) I'm
> asking to do their application for them.  I also do volunteer programming
> for several volunteer organizations, and it's the same situation - unattended
> laptop while I wander off and chat with management to tell them why it
> will take so long to do the impossible. ;)
>
You leave your laptop turned on and out of your immediate reach? Geesh.
I would NEVER leave my laptop anywhere that I didn't have it in eyeshot. It
was the whole reason I got one.
 
> As you might imagine, I have a full suite of programming tools on the laptop,
> including MS Office Pro and VB Pro, both of which are worth about $500
> apiece - I'd sure hate to lose them to a malicious cracker, or someone who
> would like a personal copy of my source code for their own use, or who just
> wants to "borrow" my secret key for awhile.
>
Business must be good, you are more worried about somebody stealing a $500
dollar program than a several thousand dollar laptop?
 
> What do people recommend as the solution for this?  Some sort of IDEA-based
> or triple-DES-based device driver would seem to be the answer to this, but
> I'm not sure which is the "best" (most reliable, fastest, easiest to set up)
> one to use.  I like the sound of Michael Sattler's encryption driver for the
> Mac, but alas, I'm running MS-DOS :(
> 
Try Lo-Jak so that when your laptop goes a wanderin' you can find it....:)