You'd be hard-pressed to find any organization that doesn't depend on Microsoft Excel. Unfortunately, this doesn't mean spreadsheets are treated as an enterprise resource, and here's where the SaaS (software as a service) movement fills the gap. A new hosted application, called eXpresso, not only brings document management to spreadsheet-based workgroups, but jumps past basic file versioning solutions by adding considerable community features including chat and simultaneous editing – all without an IT admin lifting a finger.

The Bottom Line eXpresso 1.0 eXpresso, expressocorp.com Very Good  8.5 criteria score weight Ease-of-use 9 25% Features 8 25% Scalability 8 15% Security 9 15% Management 8 10% Value 9 10% Cost: Free trial through October 2007; afterwards, monthly charge of $15 per user (volume discounts available Platforms: Internet Explorer 6 or later; Microsoft Office 2000, XP, 2003, and 2007 Bottom Line: eXpresso, a secure SaaS, enables workers to quickly create communities for sharing Microsoft Excel files. Workgroup features go beyond those available with document management systems. These unusual capabilities include change alerts, group editing with instant messaging, audit trails for regulatory compliance, and side-by-side comparison of changes. Notably, members control what edits others can make, down to the cell level. About our Reviews and Scoring Methodology

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A second major difference between eXpresso and run-of-the-mill document managers emerges when you consider the technology underneath eXpresso, which is an Oracle database. (That's not surprising since the company behind eXpresso, SmartDB Corporation, sells Oracle conversion and interface tools.) Once you upload a spreadsheet, eXpresso strips out every part – data, formatting, and cell references – and stores them in database tables. As a result, the security, management, and auditing provided by the database are available separately for every element.

Equally significant, the eXpresso developers have transformed the whole document-sharing process into a great user experience, as I discovered in my real-world tests. The process starts by inviting users to join eXpresso; after they accept, you're ready to assign rights for viewing, editing, and spreadsheet downloading.

As a file owner, I controlled who could read or change my documents, and even restricted editing to certain parts of my spreadsheets – which is accomplished simply by highlighting off-limit areas and locking them. Further, I defined different edit areas within a spreadsheet for each user.

E-mail alerts work much the same way. That is, users are notified when collaborators accept, edit, or download spreadsheets. For extra precision, I used the Track Cells feature to let me know when colleagues changed a certain cell.

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Working online closely mirrors using Excel. For instance, I just clicked cells to modify formulas or values. A few common Excel commands and options (such as summation and sort) are available from eXpresso's toolbar. More extensive edits must be done in Excel itself. Here, an eXpresso plug-in streamlines the process – letting me open, save, and change properties of online files from the Excel toolbar.

While editing a spreadsheet online, I could see which users were currently accessing the spreadsheet. The software's chat feature let me strike up an online conversation, and then several of us made real-time edits we'd agreed upon; threads of messages are then archived and associated with the spreadsheet.

eXpresso provides some functions that help organize your work. After quickly adding tags to categorize files, I easily searched for all files marked with, say, "2008 Division Budgets." Additionally, this service provides traditional folders for organizing spreadsheets.

I used the Compare feature extensively, and it turned out to be one of my favorites. That's because it shows two spreadsheets side-by-side and color-codes what's changed, deleted, or added between them.

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Another important feature, File History Reports, displayed a log of all actions performed on my spreadsheets. Likewise, Cell History Reports show every change made to particular cells. I had no trouble extending this auditing to access controls. For instance, changes to rights are logged to the database, too; this let me spot that someone had edit access to a certain spreadsheet a month ago, but that right was changed to View Only last week.

I picture Microsoft countering that collaborative features are available to Excel users through Microsoft Office SharePoint Server (MOSS) 2007, which also provides workflow capabilities. Fair enough, but the cost and complexity of MOSS outstrips eXpresso by leaps and bounds. At the other extreme, free services such as Google Docs & Spreadsheets can't match eXpresso's auditing. eXpresso also trumps these solutions with its collaborative capabilities and alerts.

Overall, eXpresso provides a very satisfying experience. And from eXpresso's road map, it appears the few gaps, including workflow, will be addressed.