Investing in a "virtual" currency seems to me to be as bad or worse than investing in fiat currencies. They are all, essentially, faith based except that your faith must be in fallible human beings behaving "correctly" in order for your investment to appreciate (at best).
Since we live in a time where cities (Detroit and others) and countries (Argentina, Venezuela, Puerto Rico, Greece, Portugal, etc.) are literally failing, perhaps today's best investments* will ultimately turn out to be ammunition and long term (storable) food. Gold, silver? Well, yes except that you can't do anything with them unless there is someone willing to take them from you (at an rate that is agreeable) in exchange for something you need. Right now I am able to count on my skills and knowledge in a barter economy if the need for one ever arises. Later, as I get older, I will have to rely more on other things and that is where food and ammo come in. And at some point I suppose that I will start to put some gold and silver aside. If they are at a good price.
But currencies? Virtual currencies? Fiat currencies? Seems like a great way to get very wealthy or very broke. I just don't need the stress. At least with a share of stock you actually are a part owner of a company/corporation that has (or should have) tangible assets. And (hopefully) profits. And real growth. But I'm not invested in stocks either these days. If I was going to invest in something traditional, though, it would be in a stock. Probably a blue chip stock at this point in my life. For right now, no.
*Also in the planning stages of building an alcohol still because, why not?