The Alzheimer's Society of Canada has a good article regarding travel. Probably nothing you haven't thought of before, but all wriitten out like a little reminder as you are preparing for a trip.
At the Alzheimers Cafe in Lethbridge cards were distributed for those who wanted them. They are a business card that says"Thanks for understanding, my loved one has Alzheimers." For more information visit www.alzheimer.ab.ca
You can email me and I can send a copy to you or you can just make your own in a program like Publisher. Nice little design, simple, but when you are in a situation where people seem confused it could come in handy to be able to just hand to someone.