Find out if there is any fellow MrExcel member in your vicinity
Take a leaf out of Rory's book:
Don't let on what you can do with Excel. Just automate all of your own tasks, pretend that they took as long as though you were doing the job manually, and then spend most of your time in the nearest pub drinking guinness (yuk!).
Domski's not too far.
And pray that said employer doesn't read online forum threads.