imo this is kinda underrated, I use it all the time and it's a real time saver for me. It seems to have a good recall for things you've been doing recently, so it'll make suggestions based on a method I just added or a variable I just declared.

Another fun one I had recently was implementing elo ranking. I'd done some reading so knew what I was doing, but based on the function name and comment it generated the whole thing for me, including all the correct argument names and object properties. Watching it pop up line by line was very cool!