Box.net will now be available in Salesforce.com CRM through tabs that will give the user access to their files stored within the Box.net environment. The tabs provide access to the user's Box.net files instead of the corporate site or the user's desktop.

Documents, presentations or rich media files may be emailed to contacts through Outlook or Google Apps. Box.net integrates with eFax. Contracts may also be sent digitally using EchoSign, a digital signature company.

Box.net shows how a service using the cloud can be disruptive to the big players in the market.

It's without question that Box.net is gunning for Sharepoint and the enterprise market. Founder Aaron Levy did an interview with Robert Scoble this week. Levy wore a no Sharepoint shirt. That says it all.

Box.net Says They Have Better Than Sharepoint 2010 Today - Watch the best video clips here

The Box.net announcement is illustrative of an overall trend for service providers to provide their applications on existing SaaS platforms.

Freshbooks, for instance, is a platform for small businesses to manage their finances. Services such as MailChimp, RightSignature and Batchbook offer their applications to Freshbooks users.

It's clear this kind of integration is gaining traction with enterprise users. Companies have seen the value of cloud services like Salesforce.com. The next step is for the enterprise to leverage applications that rest on top of SaaS applications such as Box.net.

Box.net is offering unlimited storage for companies that sign up for the service. Cost is $25 per user per month for an Enterprise account.