Have you ever browsed to a website and suddenly been invited to an "online meeting" via a pop up - if so, then that is click4assistance. You need to load this on to your server, tweak the settings slightly and then assign logins to your sales team. The best feature has to be the "invite" - this allows a member of your sales team to view a list of current visitors to your site and send one of them an invite to "chat". Standard invite messages such as - "hi, thanks for browsing our site - can I help?" work well.