I'll answer the question two ways. First, to give you the answer you're asked for: The best way to promote a brand story today is through short (under 2 minutes) video clips. If your products are being prototyped, it's an opportunity to shoot video of the process, you and your team's passion for the products, and even allow for (if you build an audience) some form of group decision making (e.g. should the first widget be red or green?)

I think also if you're creating physical products, running a Kickstarter (or similar crowdfunding initiative) is another avenue by which you can bring a product to market with a built-in audience who are enthusiastic about it's potential.

But, and now to answer the question a different way, the idea that your brand story (over the product and it's benefits/values) should be front and center might be ill-advised.

Hard to provide more specific advice without knowing more about what your products are but I hope that helps. Happy to do a call to provide more specific advice.

Read Seth Godin's post, "First, Ten."
http://sethgodin.typepad.com/seths_blog/2009/04/first-ten-.html

Then read Kevin Kelly's post, "A Thousand True Fans"
http://www.kk.org/thetechnium/archives/2008/03/1000_true_fans.php

People will become fans of your brand story if you tell the right story to the right people who already want to believe it.

Seth's book, "All Marketers Are Liars" is the bible on this.