Packages include options for: use of business address, personalised telephone answering, post handling and forwarding, access to all business services (on a pro-rata basis) and use of private offices and boardrooms at preferential rates.
http://www.officehound.co.uk

Pioneers of the Virtual Office 14 years ago offering a comprehensive range of services from a Piccadilly, London base.
http://www.virtual-office.co.uk

Use a prestigious London office address on all your professional correspondence, business cards, and letterheads and benefit from a telephone answering service. 123 virtual office was set up, to develop and support a business solution for Small and medium sized Enterprises. Our objective to present our clients, with a more credible image, as a business based in the heart of London’s westend, W1.
http://www.123virtualoffice.com