We host a telephone system (PBX) which our clients (small and medium sized businesses) access through the internet. It allows them to enjoy much of the functionality which much larger business who have their own systems can deliver. e,g, auto-attendant greetings, company directory etc. The Systems are usually referred to as PBX's (Capitalised) - hence the name of the product PBXpress. The only thing situated at the customer premises are the telephones and therefore I think the design should incorporate a telephone.
Our website is http://www.prismco.com. Like this logo to be more contemporary but in keeping with the general feel of the website. The target audience is small/ medium sized business owners/ senior managers.