Ruby and Unicode
There is library called jcode that lets you use Unicode strings, but it doesn't override the standard string length methods, so you need to know you're using Unicode, which sucks.
According to a rumors I've heard, this lack of native unicode support is tied into Japanese lack of enthusiasm for Unicode. Apparently, many Japanese are upset by the Han unification process, which uses the same codepoints for Han characters in many East Asian languages. Localized fonts can display the perfered national/regional variations, but not within the same document without tweaking.
We'll see what the future holds for Ruby and Unicode.