Best: The Korean knife we bought years ago in a folk village (museum) near Seoul. Wooden handle, curved blade, infinitely sharpenable. A Vitamix. We've had it since January and have used it at least 3x every day. Canning jars -- we use them for leftovers, food storage and lots of other things.
Worst: A blender we had that came with a spout on the side, supposedly for making drinks and dispensing them. All very well as a concept, but I don't think anything ever flowed out the spout. We gave it away to a family member who must make thinner smoothies than I do -- she loves it.
Most annoying: My cherry pitter, of which I was found, which broke while pitting a cherry. I'd like to replace it, but the new one needs to last longer.