I'm too...something...to come up with a favorite off the top of my head. The top of my head doesn't work that well. But I know what you mean...a word you just like to say, not necessarily (but could be) because of what it means, but how it feels when you say it. I'm thinking.

They're the words that, when you hear someone on tv say one, you find yourself repeating it out loud, just because you like the sound of it.