My guess is that the existing software is too cumbersome for a smaller business to use? I've been looking at this problem, too.

Law firms tend to use this software, but it really should be adaptable to anything that has these requirements. We use Autonomy WorkSite: http://www.interwoven.com/components/pagenext.jsp?topic=PROD...

But there's bound to be a better way. Web apps with solid frontends or separate desktop apps.