After seeing Apple coming out with new 13" and 15" machines with only USB-C connections, I wondered whether there are mice with USB-C. This could be a choice when you don't want or can't use Bluetooth due to preference, regulations or interference. I was very surprised that it's very slim pickings. Big brands like Logitech haven't gotten around to those, and the only one I've been able to find is this one:
http://www.trust.com/en/product/20969-usb-c-retractable-mini-mouse-black
Currently I'm unable to find keyboards with USB-C, so a good option is to get one of those keyboards with a detachable cable and simply replace it with a USB-C cable. The CoolerMaster keyboards usually (all?) have detachable cables.