These are, of course, the most recent examples in a long series of must-have services for SMB Web hosts that stretches back to SSL certification and even domain registration.

One of the simplest and most effective means Web hosts have of attracting new customers, keeping existing customers and increasing the revenue generated by existing customers is adding new services.

With the launch of its new WebDrive product last week, CM4all ( cm4all.com ) - a company already helping Web hosts fill out their value-added offerings with its Web site building software - introduced what may prove to be the next important application for Web hosts.

Serving partially as an enhancement to the company's existing content management and site-building application, but also as a significant stand-alone product.

WebDrive, says CM4all CTO Cornel Schnietz, enables service providers to deliver a hosted service similar to Xdrive, or Google's planned Gdrive service ? an online file storage system that emulates the Windows Explorer through a browser-based interface.

"It's basically the approach of having your windows explorer in the Web browser," he says, "and having all your files in some professional managed data center and professional storage system, which gives you a professional backup."

Fitting on top of an existing CM4all installation - or independently for companies already using other tools or ISPs not interested in offering Web hosting - WebDrive almost seems like a no-brainer extension of traditional hosting.

"[Web hosts] sell Web hosting space," says Schnietz. "So people are buying some space on a big storage system, which is accessible via the Internet as a Web server. And [with WebDrive] you have the same: you have some space on storage system. In this case, for example, 100MB for free, and if people run out of this space - which happens pretty fast from our experience because of digital images, and the megapixels of cameras are increasing every couple of months - they have the option to buy additional disk space."

An easily upgradeable service, the product offers Web hosts a very simple and immediate way to generate new revenue from their existing investments in infrastructure.

The model is partly designed to attract the growing audience for simple consumer-oriented hosting services, along the lines of blogging. In fact, says Robert Schovenberg, CEO of CM4all, the service can serve as a lead-in to more complex hosting services, the way something like domains might.

The interface itself offers a variety of simple browser-based functions, including a simple photo-editing application and the ability to create guest accounts to facilitate file-sharing.

"Right now there are a lot of people with photos who want to share them," says Schovenberg. "So at the moment lots of Web hosting companies are thinking about how can they get them into hosting. And the business model is designed to support this. They can give it to everyone. For starters, everyone may not be interested in Web hosting at the moment, but starting to share photos. Then the next function in the Web drive will be to take some pictures and say 'I want to have a photo homepage.'"

Through its partnership with European telecom T-Mobile, CM4all has built the WebDrive functions into that company's Web mail offerings, enabling Web mail users to quickly save emailed photos to their WebDrive storage spaces.

While there are competing products, such as the aforementioned Xdrive and the upcoming Google offering, the possibility of acquiring a Web-based storage service from a Web hosting company is an obvious advantage for existing hosting customers, and could certainly prove to be a means of attracting new customers to Web hosting services.