The weird thing was that I don't really use Gnome on other machines as I prefer KDE, and I hadn't seen the Unity desktop before (as I understand it, this is a lightweight gnome replacement - it still looks and smells like gnome to me), so there were a few things that were "missing" as far as I was concerned. Easily the most annoying is the Alt+F2 shortcut, I don't really care what GUI I'm using, I mostly just run things from that! I also realised that I now had workspaces, but that there was no keyboard shortcut to switch between them (I don't use a mouse, so it's keyboard or nothing for me).
Enter a wonderful utility called gnome-keybinding-properties.
Gnome-keybinding-properties allows you to create and configure keyboard shortcuts for your system; run it from the commandline and it will pop up a little window with all the shortcuts in. There's no access to Alt+F2 but I mapped a program called gmrun to Alt+Ctrl+Space which seems to do exactly what I expected. I also added shortcuts for the workspaces to be Ctrl+F1-F4 which is what I'm used to on my other machines and I felt quite at home :)
I threw the netbook into an oversized handbag and went off to Belgium to phpbenelux to deliver my keynote, and the machine did exactly what I needed all weekend despite some fun and games with patches needed for joind.in. Thanks, Ubuntu!