So, being a miner of small repute, mainly cos i like to play with old hardware and fit it to a new purpose, and i also hate to throw something away if i can use it for something else....I've been following this FPGA trend closely as it's pretty interesting what folks are up to..
So much information is out all over the place so i thought I'd condense it down purely for my own needs, but you guys can use it also.
General Comparison site :http://bitcoinfpga.com/General FPGA Performance Analysishttp://www.wikifpga.com/index.php?title=Performance_Analysis ( if anyone has something more up to date.. please let me know )
Butterflylabs Singlehttp://www.butterflylabs.com/product-details/Raw performance: 832 Mega Hash / second (+/- 10% running variance)
Power consumption: 80w at load
Cost: $599 + Shipping
ZTEXhttp://www.ztex.de/btcminer/http://stores.ebay.de/ZTEX-Shop/ 
https://bitcointalk.org/index.php?topic=49180.01.15x Version Board
Cost: 309.51EUR + Shipping
205~215MH/s @ approx 9.4W
FPGA Minerhttp://cablesaurus.com/index.php?route=product/category&path=10Dual FPGA X6500 Mining Card
Avg. hashrate: 400 MH/s Max. power draw: 20W
Cost: $580.00 + Shipping
FPGA X6000 Mining Card
( DISCONTINUED )X6000 200 MH/s @ 10 W
Cost: $390 + Shipping
FPGA development board "Icarus"https://bitcointalk.org/index.php?topic=51371ngzhang
Technology: Spartan6 -LX150 -2I (or -3C)
speed (MH/s): 380
$: 569 (1) / 469$ (multiple of 30) (-5$ if you do not need the adapter, recommend for bulk orders, they are heavy)
W: 4.5 for idle / 19.5 for full load. (notice this is the on wall power, include the adapter losses)
There are others... but I've limited it to these as they are probably the most serious players in the market to date.
So this is just some info scanned from the various forums and such into one place. I'm been looking at other FPGA set-ups, and whilst they all look pretty intriguing, I'm no where near closer to figuring out which one look the best in terms of economics.
From the comparisons, and from the set-up cost, per unit, vs eventual power usage I'm kinda leaning towards the ztex boards as they offer the best power conversion rate to btc. The best thing i like about this is the lower power consumption requirements, which might fit neatly into my Solar experiments I'm going to start in the summer.
I think, in terms of space taking motherboards, psu, graph cards, worrying about the heat generation, noise levels, safety concerns, power usage, the FPGA does have the ability to clear my entire spare room of junk boards currently grinding away to earn a pittance....
if i think real hard ( which is a rare event ) i'm pretty sure that after all the 5870/6790/6990 setups, planning, tubing for vents, extractors, ice trays, kitty litter trays and weird 2am confabs... a small fpga miner means i can have my spare room back....
trouble is... at roughly 400euro a pop its not a cheap alternative... but the power savings over my own rigs would in the long run save me power and increase btc profits... but they aren't all that resalable after im done with it......yeah, i know.. there's always resale value in ati cards.. but seriously... once im done with mining... i'll just start tinkering with something else that will end up costing me money, time, and patience lol
So i've also done some research into China for FPGA setups... i found a few that have ready made FPGA Spartan6 board with USB.... thing is, i haven't found out yet if a i need some jtag conversion box to talk to them yet.. ( im a FPGA n00b ) so the search is on.. .i suspect at some point, in china somewhere in Shenzhen a plan will be released to make them available en mass... when that happens... i suspect difficulty will rise 10 fold 6 months after that. Then im probably going to be looking for a new tinkering hobby.
Comments, flames, buckets of water all welcome... but please refrain from throwing rotten fruit.... aim it towards my biomass generator please.
Salt 'O' the rock
