Dan Bricklin fostered the PC revolution when he helped create VisiCalc for the Apple almost 25 years ago. It and its successors, Lotus 1-2-3 and Excel, were the original "killer app" for PCs.Bricklin went on from that success to give us the granddaddy of presentation programs in Dan Bricklin's Demo - used to produce demonstrations, presentations, simulations and prototypes of computer programs. It's still being sold. While not a killer app, it was a neat idea.Now Bricklin has a new idea that involves small business and the directory arena, and he might just be on to something yet again.Small & Medium Business Metadata (SMBmeta) is an XML specification for identification and location information for small, primarily bricks-and-mortar businesses. Third-party information aggregators could harvest the data with robots and build business directories that let consumers easily find the goods and services they seek. See\u00a0smbmeta.org\u00a0for details on how it will\/should work.Burton Group's Jamie Lewis\u00a0says he thinks this is a better method of finding businesses and services\u00a0than the IBM\/Microsoft\u00a0Universal Description, Discovery and Integration\u00a0technology, which up to now hasn't taken off and probably never will. Lewis calls the concept behind SMBmeta a "loosely coupled, self-organizing directory," and offers the possibility of joining the SMBmeta concept with peer-to-peer technologies.In many ways, the concept encompasses what I've called the "personal directory"\u00a0 and is similar to the\u00a0".DIR" top-level domain\u00a0Novell proposed a few years ago.In fact, the .DIR specification is remarkably similar to the SMBmeta specification in scope and direction. But we'll need to encompass more than just small to midsize businesses for this to ever graduate from being a simple niche product. There are some problems that need to be addressed, such as scaling. One smbmeta.xlm file per Web domain would have to include a huge number of lines for the locations of every McDonald's restaurant, for example.A way also will need to be found to extend this concept to individuals and a way to simply federate the data (on a dynamic, ad hoc basis) and aggregate it. I'll explore these concepts more in the Network World "Identity Management" newsletter over the coming weeks (sign up for the Identity Management newsletter).Just as VisiCalc begat Excel and "Demo" begat PowerPoint and Flash, SMBmeta could be the prototype for the next killer app.Tip of the weekVisiCalc was released for the IBM PC in 1981 - and it still runs on today\u2019s machines! Head over to\u00a0Bricklin's site, where you can download a copy and experience what was the cutting edge of PC computing some 20 years ago.