The company today announced its fourth Mystery Box sale will start at 12:01 a.m. March 10th. For $1 plus $5 shipping, customers can purchase a box containing a variety of items. The mystery, of course, is what’s inside. And this time around, two lucky customers will open their boxes to find an Xbox 360 or an Advent Heritage Series five-speaker home theater surround sound system. Not bad for a buck.

Since launched the first Mystery Box last year, participation in the midnight buying game has increased with each successive Mystery Box. The company sold 350 Mystery Boxes the first time, 1,000 boxes the second time and 2,000 – in less than eleven hours – the third time. is keeping the number of Mystery Boxes available on March 10th under wraps, but co-founder Joe Modicamore did say it will be considerably more than 2,000.

Considering the popularity of’s Mystery Boxes, buyers would be well-advised to get to the site and make their purchases as close to 12:01 a.m. as possible. Previous Mystery Boxes have included a variety of items including, but not limited to, branded items, MP3 players, digital compasses, remote controls, portable hard drives and wireless mice. Each box is randomly packed and shipped. While the minimum Mystery Box has an approximate retail value of $20, the top Mystery Boxes on March 10th will be worth over $650.

And that’s what keeps buyers coming back to’s Mystery Box nights. Aside from the element of surprise, there’s always the chance any buyer could find an Xbox 360 in his or her $6 box. waited to announce the upcoming Mystery Box night until its servers were upgraded to handle the expected traffic. During the last Mystery Box night in November (, over 20,000 people visited the site; the company expects over 50,000 unique visitors on March 10th. But until those Mystery Boxes start arriving on customers’ doorsteps, it’s anyone’s guess what a dollar will buy this time.