Web hosting firm Fasthosts is offering Microsoft's Office 2007 suite using a software-as-a-service delivery model.

Customers can obtain the productivity suite as a download direct to their PC for £4.99 to £19.99 per month, avoiding the upfront costs and discs involved with the boxed product.

The downloadable Office suite is exactly the same in appearance and functionality as the boxed product, but runs locally on a user's PC and is verified with Fasthosts when the PC goes online.

Users have to be online every time they use the product at this stage, although an 'offline version' is in the works.

Mark Jeffries, chief technology officer at Fasthosts, said: "Our Office package is an excellent way to obtain the latest versions of the software we all need on a pay-as-you-go basis. Its low monthly cost and easy installation will suit a great many home and business users."

Fasthosts is offering four versions of the productivity suite. Office Standard includes Word, Excel, Outlook and PowerPoint, while Office Professional Plus adds Publisher, Access and Infopath.

Households with a user engaged in educational activities qualify for the Student Edition, and can opt either for the Standard edition at £4.99 per month or the Professional Plus version for £6.99 per month.

Users without a dedicated student on the premises can lease the Standard edition for £14.99 a month and the Professional version for £19.99 a month.

The software-as-a-service concept allows the provision of software by a vendor for delivery or use over the internet. This means that customers do not pay for owning the software but rather for using it.

This enables users to pay for software gradually, and benefit from service benefits such as free updates and any support provided by the vendor.