With only four days out until the next difficulty change, BitcoinWisdom predicts that for the first time since ASICs appeared, the Bitcoin mining network will shrink over a two-week period.

Manufacturers like Bitmaintech and Spondoolies are seeing a surplus of unsold stock, so they're getting in the game to offer deals for Bitcoin Black Friday.

There are a whole host of mining related deals which can be found on Bitcoin Black Friday's website.

Are you interested in purchasing a Bitcoin miner, but have no idea where to start when it comes to sorting through the options that are available?

One of the better-kept-up lists I've seen floating around the internet as to what deals are available on the market out there can be found at RigWarz.com, where currently the Jackson SP20 takes the top spot. In fact, since it's Black Friday, you can currently pick up the SP20 even cheaper at $695 rather than the $795 which is listed on RigWarz.

In addition, ASICSPACE is offering $5/KW/MO off our hosting price through next Monday! Just fill out a form with the coupon code BBF5OFF.

Please note that the ROI figure listed on Rigwarz is for comparison purposes only: it's a metric used to sort the rigs by return based on current market conditions, but no guarantee of ROI.

In general, the more expensive your electricity is, the more it makes sense to go with more efficient miners like the SP20 over a less-efficient but cheaper in terms of $/Gh miner like the Antminer S3+.

Another thing I should note is that Bitmain has a deal floating around right now, where if you score a coupon, you can get $400 off the S4 and $50 off the S3+.