One of the best investments I've made in the past 15 years was to buy impact wobble sockets. Sometimes known as "universal" or "flex" sockets, they allow you to turn a nut or bolt without being perfectly in-line with the axis of the fastener. Regular chrome wobble sockets are great for turning fasteners by hand in tight spaces, but impact-style wobble sockets really shine on impact wrenches. Especially battery-powered impact wrenches.
I've got a rack of 3/8" drive impact wobble sockets that I use on my 3/8" drive battery-powered impact that are literally polished and shiny because I use them so often. A coworker clued me in to using impact wobble sockets. I thought it was overkill to have them, but once I discovered the convenience of not having to perfectly align the battery-powered impact wrench with the fasterner I quickly became a believer.
If you've got someone on your Christmas list who frequently uses a battery-powered impact wrench, especially a 3/8" battery-powered impact, a set of standard or metric impact wobble sockets would make a great gift. They may be politely grateful on Christmas morning, but in a month or so, after they've used them for a while, they'll sincerely thank you