My nephew has recently developed an allergy to nickle. Does anybody know of a nickle-free electric guitar string?
Check out Elixir's Polyweb strings. They're coated with a very, very thin layer of plastic, so that should keep your nephew healthy and rash-free.
There are quite a few. Ernie Ball makes several stainless steel strings, as do a few others. You might also want to look into coated strings like Elixir and Cleartone.