A lot of people go after the African Greys and Amazons for their speaking abilities. However, I think budgies are the real champions. I'm not sure if this is correct or not, but I read somewhere that it was a budgie who could mimic the most words.
Now, it's really obvious that budgies are just mimcing, and not actually understanding what they are saying, but I still think it's really adorable that budgies can learn to say the amount of phrases and words that they do.