The Oculus Rift has been updated in the form of the Rift S, but that doesn't mean there are still countless original Rift CV1's being used for an incredible VR experience. Part of that optimal experience involves awesome accessories that range from basic things you ought to have on hand, to the absolute coolest gadgets to take VR to futuristic heights.
The Touch controllers included with the Rift each require an AA battery to operate. Speaking from experience, you're going to want to invest early in some rechargeable batteries to save money in the long run. This pack includes a wall charger that can handle four AAs at once, so you shouldn't have any downtime while waiting for a charge.
This six-foot extension cable from Monoprice is essential for anyone looking to get a room-scale Rift setup going. Sure, the built-in cable on the head-mounted display is lengthy, but while you're twisting and turning in your VR space, you can run out of room quickly. To keep your PC from toppling or your headset from coming off of your head, add an HDMI extension for plenty of cable length and a worry-free experience.
Toting your Oculus Rift over to a friend's house can be a bit scary. You don't want to just toss it into any old bag or box, and you definitely want it to have some padding. This case from Hyperkin has a bunch of modular, padded compartments that can hold your sensors (once you unscrew them from the stands), Touch controllers, headset, and cables securely and safely.
If we're picking a few accessories
Enjoying the Oculus Rift with a dual-sensor setup is one thing, but adding a third or fourth for true room-scale VR allows you to get the best experience possible. You'll find that games are more immersive and you'll no doubt experience far better tracking than before. They're getting tougher to find at a reasonable price, but Oculus still has sensors for sale. You'll be glad you invested once you have everything set up.