In Switzerland we have 4 official languages. So language Fallback is a topic in every project here. I am so happy the in Sitecore 8.1 we meet new Language Fallback features. Till now we were using the partial language Fallback module of Alex Shyba.
Here is the most extensive blogpost series about this topic:http://www.sitecore.net/learn/blogs/technical-blogs/elizabeth-spranzani/posts/2014/10/fallback-followup.aspx
Addition helpfull stuff:http://sitecoremadness.blogspot.ch/2015/04/language-fallback-word-of-caution.html