Innocuous- Having no adverse effect, harmless
Rhododendron- Any of various evergreen shrubs of said genus, having variously colored flower clusters
Vacillate- To sway from side to side. To swing indecisively between courses of actions or opinions.
Ellipsis- the omission of a word or phrase required for a complete syntactical construction, but not necessary for understanding.
Phlebotomy- The medical practice of opening a vein by incision or puncture to draw blood.
Those are some winners I've come across lately. Innocuous I've always loved, and often used in ways it doesn't actually work, but I like the sound of it. Rhododendron I just like to see in print. The others I like mostly because it amuses me that there are words that mean something so specific, particularly ellipsis.
Jonb, I got Quiz once where the Q was on a triple letter and the Z was on the triple word. I don't remember what the total points were, but that was certainly my best ever.