Just discovered obsolete kana!

I was in the middle of finding the translation for the word いた when the Microsoft IME offered an alternative kana translation that looks like this： ゐ. This was my face (O_o) What is that!? So I hurriedly typed it into google to find out more and Wikipedia tells me this is one of a few obsolete kana and it is pronounced "wi". Then I discovered 'we' : ゑ. I especially like this one, it looks kind of like an Egyptian hieroglyph. I had always wondered why there were only 2 kana beginning with the 'w' sound. It makes me wonder where 'wu' is now...I need to do more investigating.