The free option includes a one-time download of the first nine tracks from Ghosts I – IV encoded at 320 kbps MP3s, a 40-page PDF booklet detailing the release and a digital extras pack containing icons, wallpapers and other graphics.

For $5 you get all 36 tracks (yes, that’s right, 36 tracks) in a variety of digital formats, including fully-tagged MP3 files encoded at 320 kbps, FLAC lossless and AAC lossless, plus the aforementioned 40 page PDF book and digital extras pack.

Moving up to the $10 price gives you everything included in the $5 option plus a double CD to be mailed later.

But wait, there’s more.

The $75 option includes the two audio CDs, a data DVD that includes multi-track session files for all 36 tracks stored in WAV format so that the tracks can be reconstructed and remixed, a Blu-Ray disc containing 24 bit 96Khz high-resolution audio stereo mixes, plus a slide show that plays with the music. The $75 selection also includes a book containing 48 pages of photographs by Phillip Graybill and Rob Sheridan.

Then there’s the $300 Ultra Deluxe Limited Edition, which includes everything mentioned above plus a four-LP set imprinted on 180-gram vinyl in a fabric slipcase and a fourth book containing two exclusive Giclee art prints. Each limited edition package is numbered and personally signed by Reznor.

The drill is simple. Order the desired package and NIN.com sends an e-mail link for the download.

The Ghosts I – IV download went up on NIN.com on Sunday and was quickly jammed with orders, but a message from Reznor indicates that any congestion problems will be eliminated as soon as possible.

“We’ve been adding more servers to accommodate the unexpected demand and we expect to be running smoothly in the next few hours,” Reznor posted on NIN.com. “In the meantime, if you’ve had any problems with downloads from the Ghosts site, don’t worry – you’ll be able to use your download link again when the site is more stable. Thanks everyone for making this such an immediate success.”