First time my code is on par with the top result. I usually feel like a noob coder at this point but not today. Woohoo!

nice code

Nice, good job!

This is brilliant. Thanks!

Can it pass the test such as solution(["a","b","c"],3,"a")? I think it should return a

Does this qualify as "easily?"

signmod = index < 0 ? 1 : 0

(index.abs() < items.length + signmod ) ? items[index] : default_value

@wchargin, I think it's fine to use the ternary ? operator here. Is that what you meant by this isn't very Ruby?

See http://stackoverflow.com/questions/4252936/how-do-i-use-the-conditional-operator-in-ruby

This isn't very Ruby. (1) you should use the builtin fetch, (2) if not, you should use unless statements instead.

I did the same thing without recursion. Now I feel bad of my solution. Yours is just brilliant. Good job =)