This video walks through two sample Roslyn Analyzers.
One analyzer gives squiggles where you could improve your code with the new C#6 language features - nameof(), ?. and primary constructors.
Another analyzer gives squiggles for a XAML performance tip - allocating repeated heap allocations of PropertyChangedEventArgs objects.
Source code for the analyzers can be found at the Roslyn discussion thread for this sample: http://roslyn.codeplex.com/discussions/562202