Recently I have heard a number of people (Chris Kunicki and LauraJ for instance) musing why there isn't an InfoPath viewer application available to allow people without InfoPath installed to be able to see a read-only view of the data from a filled-in form. I don't have the answer to that I'm afraid, but I do know that there is a KB article and an article in the InfoPath SDK that describe design-time techniques that enable a user with just Internet Explorer installed to view completed forms.
Despite that with a bit of free time last week I decided to see how easy it would be to put together a little app that would enable InfoPath forms to be viewed without any design-time modifications. A few hours later I had created this simple InfoPath Form Viewer application.
Unfortunately I am unable to devote any more time to working on this, however if you like the idea of this sample and you have time to enhance it further, please feel free to start a GotDotNet workspace with this source code. I only ask that you post a comment here linking to it so that others can get access to the latest version.