Do you have projects in mind? What languages are you most used to? That might help you decide. Learning a very different language is fun and useful.
Yes, that's one of my main motivations. I'm comfortable enough with Python, Java (comfortable doesn't mean I enjoy this one) and C.
> Do you have projects in mind?
Yes, both are solely for the purpose of enrichment of my current set of skills and knowledge: - Source control system that is a "lite" version of git. - A bit torrent client.