Faraday cage protection

Any of you survivalist types using one to protect your delicate electronics from a possible EMP? I’d like to build something nicer than an insulated trash can so I have a few questions.

Would a ferrous metal be most effective?
If using a metal mesh, what’s the maximum hole size?
What’s the deal with grounding? Some say it’s a bad idea because it can act as an antenna.

Got an old microwave? If so, you might be able to use that as an effective faraday cage.

This book has lots of info on how to build multiple varieties, their effectiveness, and is written by a PhD in electrical engineering.
http://www.amazon.com/Disaster-Preparedness-Attacks-Storms-Expanded/dp/1478376651/ref=sr_1_1?s=books&ie=UTF8&qid=1378868269&sr=1-1&keywords=Disaster+Preparedness+for+EMP+Attacks+and+Solar+Storms+(Expanded+Edition)

I’d like it to be large enough to hold more than just electronics (about 10 cu ft) and well-sealed. A mesh bag would be a handy thing to have, also.

Thanks luvlites. I might have to get that if I can’t find any free factual info.