I once heard that the record for natural languages is 104 and wondered how many programming languages it's possible to command fluently.
Well, records aside, it would be interesting to know the distribution for the HN clientele.
How many programming languages are you able to use effortlessly to produce nontrivial programs?
Likewise, anyone capable of writing a program with Ruby should be able to pick up Python in a day or two. Java and C# are, for the most part, just a few syntax conventions apart. What's more impressive is if you can code, competently, in a pure object oriented language as well as a pure functional one.
If you already know Ruby, I'd wager your time would be much better spent learning Clojure or Haskell than Java or Python.