I was reading LuminousLogic on his foreign-wife's-isms :-). It's interesting. Not as funny as it might be, but it's an honest post, not one that begs for people to laugh.
Where I live we're all foreigners (when compared to the english and the english-speaking americans). We also speak at least two languages (I speak three, some chinese and east-indian immigrants to the Philippines speak four or more). So we all have these foreign-isms.
Foreign-isms make for richer conversation. One can switch between languages in the same sentence, choosing the words that are better in whichever language. That only works when speaking to someone who has the same (or a superset) languages. The rest of the time, using a funny sounding foreign-ism from a language that isn't shared can be cute (if done sparingly). Or so my wife says :-).