If you're attending Comic-Con, read this page of tips and advice — and I'm going to quote this one because it's so important…
The barcode printed on your badge may include your name, address, phone number and email address. If you allow someone to scan that code, you may be releasing that information. Don't let anyone scan the barcode on your badge, unless you want them to have your name and address.
And here's one more from me: Go outside. If you're in that building for hours on end, take a moment to walk out on the back terrace where there's a lovely ocean view and actual air. It's a great remedy for Convention Fatigue.