How to share a common linux terminal that can be used remotely by 2 or more users ?

I want to code/debug collaboratively on a shared linux terminal (so that both parties can see what is being typed into it, and its output) with someone in a remote location. What is the best way to achieve this ?

Options might be:

1. Setting up a tunnel that would allow me to VNC into my partener's system. Is this possible wi开发者_运维问答thout using proprietary software ?
2. Using a web-based terminal, which allows limited disk-space to upload a source code file, and then compile/debug it (don't even know if such a service is available)

In case option 2 is not available, what is the best way to set up a publicly accessible (over the internet, but secure) VNC in ubuntu ?

You can achieve this by using ssh + screen.