I suffer at the office with java-orthodox package names like com.company.umbrella.project.product.util.
Also, tabs instead of spaces. I recently joked that this is why our team works in different time zones separated by vast expanses of desert wasteland, to avoid interpersonal conflict.
Scala's loosey-goosey package names, compilation units and file locations are not just hip style, they are an expression of true sanity, or at least says that this is something we shouldn't drive ourselves crazy about.
I'd go for a "scalang" prefix to announce "I favor a scala API and probably you'll never call me from java or groovy".
Maybe lightbend could write a little sbt plugin that would consult a registry and then register my package name scalang.funstuff when I publish my "com.github.myname.funstuff" jar.
The contraction "scalang" sounds like a world word, and not just a west european word, and for that reason I'd favor its adoption for other purposes, too.