Remote Bonjour Connection I currently use a code editor called Coda.

It uses Bonjour to offer collaborative code editing over a local network.

I am going to be travelling for the next two months and need to occasionally screen share with a colleague. My internet connection will change day to day, theirs will be relconstant.

What is the best way to use bonjour remotely, do I need something like ShareTool?
If you don't have a VPN or something similar then you're not going to be able to use Bonjour. The multicast packets won't get passed from your colleague's network on to the internet (otherwise you'd see everyone in the world using Coda!). You need a VPN, possibly ShareTool (although I haven't tried it) or a local machine you can remote access.