Just a couple weeks after pre-orders went live and just three days after it started shipping, the Samsung Gear VR headset has already sold out online.

Look for it on Amazon or Best Buy's website, and you'll see notices that the first virtual reality headset to be made widely available to consumers is "temporarily out of stock" or "not available," respectively.

Simply put, the Samsung Gear VR has caught the attention of virtual reality enthusiasts in a big way.

Even though the smartphone-based VR headset is limited in features compared to what's coming in 2016 -- namely, the first consumer release of the much-vaunted Oculus Rift, the Valve and HTC VR collaboration, the HTC Vive, and later, Sony's PlayStation-ready Morpheus -- demand for the Samsung Gear VR has been through the roof.

Here's why: It's the first, and it's (relatively) cheap, if you already own one of the four Samsung smartphones that powers the device.

The Samsung Gear VR is selling for $99.99, which is practically a stocking stuffer, especially compared to the upcoming 2016 VR options that will likely cost at least three times as much.

If you're looking to pick up a Samsung Gear VR, your best option is to order it from Samsung directly. The company hasn't put up any notices saying it's sold out (yet), and Samsung is offering free shipping through Nov. 30 to boot. According to GSMArena, procrastinators might still have another option later, when T-Mobile begins carrying Samsung Gear VR in stores later this month.

As far as the sold-out status at Best Buy, Amazon, and the question of whether there will be enough Samsung Gear VR headsets to go around this holiday shopping season, a Samsung spokesperson gave TechCrunch the following statement:

"We are delighted with the overwhelmingly positive response Gear VR has received from reviewers and eager buyers alike. We are working hard to fulfill all orders as quickly as possible."

The Samsung Gear VR is a headset that requires the Samsung Galaxy Note 5, the Samsung Galaxy S6 edge+, the Samsung Galaxy S6, or the Samsung Galaxy S6 edge to power the device. All four devices offer quad HD resolution (2560 x 1440p).

Slip one of Samsung's 2016 flagship smartphones into a slot on the headset, and the smartphone's screen turns into your window into 360-degree panoramic views, using the phones accelerometer to track the movements of your head.

A built-in trackpad on the Gear VR provides navigation through menus. Gear VR comes with over 100 VR-ready experiences, including games, apps, and a virtual theater for Netflix, Twitch, movie trailers, and movies available through the Oculus Store.

The headset doesn't track positional motion -- like standing up, crouching, or sitting down -- as the Oculus Rift and HTC Vive promise, so this VR is meant to be experienced sitting down.

Samsung has a Bluetooth gamepad, sold separately for $70, the selection of VR games available for the Gear VR at launch, but it's also sold out at the moment.