Select Wisely offers a very valuable service: laminated wallet-sized cards translated into over forty languages, describing your food allergy or other health condition. This looks like an invaluable resource if you or your child is traveling internationally. Along with common allergies such as peanuts and shellfish, they also have cards for eggs, gluten, milk, latex, Type 1 diabetes, asthma, and penicillin, among many others. The languages available include everything from Arabic to Vietnamese. They accept special orders, and can also send you a document over email which you can print and carry yourself, or show to people on your smartphone.
As one of the (many) testimonials on the site put it:
My 12 year old son has gone on 2 school international tours using your food allergy cards. 5 different countries with no allergen exposures. Parents do not travel with the school so so having the allergy cards is a great worry reducer.
This could easily be a lifesaver for some people. The prices range from $4 to $15, depending on the complexity of the document. That seems like a very reasonable price to pay if this is a major concern and you have any worries about communication barriers.
Thanks to Esther M. Friesner for the link.