I just went through this last week trying to get my iPad to connect, so maybe I can help
From the client computer you can't use 'localhost' as that will try looping back to the localhost of the client computer.
You have to use the ipaddress of the host computer. Go to Start/Run and type 'cmd'. In the command window that opens, type 'ipconfig' to get the ipaddress of the host machine.
Also, on your host computer, you have to have your firewall open the port you are using. Whether it is Windows firewall or some 3rd party, there is probably something in the settings that lets you do that.
And lastly, on your host machine you need to edit a setting in your Apache httpd.conf file. Here is the section where I had to change:
#
# Controls who can get stuff from this server.
#
# onlineoffline tag - don't remove
Order Deny,Allow
# Deny from all
Allow from all
Comment out 'deny from all' and add 'allow from all'
That allowed me to connect any machine on my home network to the localhost of my host machine. I assume the same types of changes would have to be made in your environment, unless node/socket.io requires something else. Hopefully that helps.