I suppose its my turn to contribute something. If you are into Cryptonight mining, which it sounds like a few of you are, check out this Gigabyte mini-pc for $250: https://www.newegg.com/Product/Product.aspx?Item=N82E16856164036
You won't be adding any graphics cards (unless you are using eGPUS) but this thing will hash at 614 H/S. You might be wondering how its possible to get that kind of performance out of a cpu with a 6 mb l3 cache. The game changer is that this processor has an embedded Iris Pro GPU with a 128 MB L4 cache. XMR-Stak recently included an optimization to take advantage of this cache space. It should ROI itself in 2.5 months. You have to provide your own ram and HD, but it does come with a wifi card so you could put this thing anywhere.
...and it's already almost doubled in price.
Thats a third party seller "Fateka". Not Newegg. It likely sold out from Newegg. Or Fateeka bought out Newegg and is looking to profit.
The latter. The link bypasses the sold out page and takes you directly to their third party offers.
EDIT TO ADD: also the average ebay price jumped up from around $260-80 just a few hours ago to $340 and up now.
EDIT2: I WAS able to find an i5 model at a reasonable rate (comparing the two on the Gigabyte page, the specs are identical other than the CPU i class, so I'm assuming it should come pretty close to the above estimates). Picked up one to play with.