I have an HTC EVO 4G and I've been using the manufacturer's supplied app for wireless tethering. It works great but is missing are several key features I require:
Is there a way to enable this functionality?
One thing you could do would be to set up an Amazon EC2 Ubuntu server instance as an OpenVPN server and then use the OpenVPN client app on your laptop. Then you have to forward everything incoming to the server to the client interface IP address of the OpenVPN client running on your laptop.
I haven't done what you are wanting to do--the port forwarding part--but I easily could with the existing OpenVPN setup with some iptables tweaking to direct traffic to the client.
This sounds more complicated than it is, but you still need to be somewhat comfortable with the Linux command-line to get thru all this.
As far as the cost of the EC2, it's normally ≈$15/month, but I think they still have the deal where if you've never signed up for Amazon AWS before, then you can get a year for free.
Your own personal OpenVPN server is nice to have for when you are overseas and want to watch USA tv shows online (b/c they refuse connections from outside the USA), or if you are in a place where content or services such as Skype are blocked (such as on planes). It basically makes selective blocking of services impossible.
If you have specific questions, just send me a message.
