I love small, focused Web apps, but I believe the most successful online applications will be suites, not one-trick wonders. The is especially true for small-business applications, because who wants to learn a dozen different user interfaces, keep track of multiple logins, and store data on multiple servers?
An example that supports this thesis is the small business suite, Veetro, an ambitious collection of integrated small business modules. Veetro is built on a fairly rich database structure that should handle almost any small business process. For example, the timesheet application feeds into the invoicing system, which is just what you want if your aim is to streamline your accounting and billing. There are Web site form-building tools that will feed into a leads management application. And so on.
Unfortunately, the interface is cumbersome. Without a step-by-step guide from the CEO, a few medium-complexity tasks would have escaped me. For a person accustomed to well-evolved applications, such as Quicken, and used to seeing elegant (if oversimple) "point" applications, such as Blinksale, Veetro's complex user interface seems old-school. But to be fair, even a very small business is a complex network of interlinked tasks and information, not easily crammed into a one-button UI.
Veetro is worth experimenting with if you you want an integrated back-office application for your small business and you have the time and energy to devote to learning its complex user interface.
Veetro is free (ad-supported) for one or two users in a business. For larger companies it costs $70 per month.