I'm also REALLY jazzed about my newest $20 Amazon.com purchase -- a big ole funnel normally used for oil changes on cars up on lifts. It's huge -- 15" around, but it fits an entire 50lb bag of salt from IO/RC all at once, and the funnel end passes salt through at a slow/medium pace to maximize mixing efficiency. There is even a multi-section divider at the bottom that keeps salt from clumping in the middle and stopping the flow.
Now I can pour in 50lb of salt, go do testing etc. for a few minutes and come back -- the salt is gone and I can add another bag if I choose. No more measuring cups or sore arms from slow pours!
Big Funnel for Pouring Salt
Things like that are certainly handy. Like you, I was tired of measuring out salt but figured out that a bag of IO will make 46 gallons of saltwater at 35ppt.