Earlier I pointed out a method for identifying the MM blocks.  They have a consistent and unique coinbase format.

According to the wiki....   "The body of the block contains the transactions. These are hashed only indirectly through the Merkle root. Because transactions aren't hashed directly, hashing a block with 1 transaction takes exactly the same amount of effort as hashing a block with 10,000 transactions."...   

While there is apparently no additional work involved to do the (indirect) hash of a 10,000 transaction block, there is obviously added work involved in building and processing a 10,000 transaction block.  A miner ignoring transactions would appear have some advantage over a miner including transactions.  With the relatively small number of transactions per block processed currently, the amount of extra work may be negligible, and not produce any practical advantage. 

I noticed the mystery miner's blocks coinbase values follow a consistent format... a constant 4 byte field of '87320b1a' followed by a 3 byte field in which the last byte is either unchanged or increments (usually by 1) from one block to the next.  Prior to the samples documented below, I saw the last byte of the 3 byte field counting from x'10' through x'20' (skipping x'1c').

I don't know the significance of the 4 byte value of '87320b1a', but I noticed it is commonly found in the coin base of many blocks besides the mystery blocks.  The 3 byte coinbase field is possibly unique to the mystery miner.

Sample 3 byte mystery miner coinbase fields and block numbers:

931f21  171886
accc21  171900
bc1922  171908
411f22  171910
a32422  171911
[at this point the counter reset to 00 apparently]
1a8400  171931
489700  171936
93a300  171938
280302  171964
e42102  171967
5d2802  171968
4f4502  171971     

fwiw:  I noticed that on my Windows machine, if a video (e.g. youtube) is playing (even paused), my hashrate drops by approximately 67%. 

1)  It is probably true that people leaving game currency in their accounts don't have much.  However, I've witnessed many people abandoning land to Linden Labs that is worth quite a bit of game currency.  It seems unlikely they would also abandon significant sums of game currency, but it's possible.  Linden Labs sometimes cancel accounts that violate the Second Life Terms of Service, and confiscates their assets.  Abandoned assets enhance Linden Lab revenue, but it is not known to what degree. 

2)  Linden Labs makes a market in lindens/USD on their exchange and maintain a very steady exchange rate.  That is why there is a big difference in volatility between the lindens/USD value as compared with bitcoin/USD.   As a long time Second Life resident, I've been able to keep Linden currency in my account without experiencing any significant change in value (as measured in USD) over a period of years.

3)  Yes, I would think LL would be likely to run a btc/USD exchange if Second Life were to switch to bitcoin.    However, in the face of competition from lower fee exchanges, it seems unlikely it would be as profitable as their current exchange;  and making a market, which is simple for them now (and apparently quite profitable), would become more complex and riskier. 

Personally, I wouldn't mind if Linden Labs did switch to bitcoins or added bitcoins as an option.  Considering the software changes involved, potential reduction of exchange revenue, and possible disruption to the Second Life economy, I doubt they will consider making the switch unless someone can come up with some offsetting benefits.     

Out of curiosity, I analyzed some of the transactions on the blockchain following the theft.  It's my opinion that a small amount of tainted coins (100) were moved to the Virwox exchange shortly after the theft.  Being a Virwox customer, I deduced this through knowledge of typical Virwox transactions, and not with any actual confirmation, so I could be mistaken. 

The Lindens run their own exchange for lindens/dollars and are market makers, maintaining a stable valuation.  This appears to be a valuable profit center for them.  It may be somewhat problematic for them to make a similar market in bitcoins.  It is unclear what effect an unstable game currency value would have on the Second Life economy. 

Some people leave Second Life permanently without exchanging their lindens for cash.  The Lindens ultimately benefit from these unclaimed funds, which would not happen with bitcoins.

The Lindens have been known to seize funds for various reasons, such as violations of Second Life terms of service.   The Lindens recently seized funds owned by "The Rock Trading Company", one of the two SLL/bitcoin exchanges.  Why this was done and whether they will get their funds back is unknown (to me).   

The customer can mitigate this power of seizure of funds by avoiding maintaining large sums of currency in world.  However, it seems unlikely the Lindens would relinquish their control of the currency. 
     

Interesting.. I've been mining since August on a Windows Vista machine with Microsoft Security Essentials and had no problems.  I haven't added bitcoin to the "Excluded processes" list.  So, it would seem the problem doesn't affect every machine running MSE. 

When it is cold outside, a portion of the electric cost can be written off as supplement heating.

I've been using an XFX 6870 since August.  It's worked great...  the only issue I've had is the fan is a rather loud during mining as I increase the fan speed to 75% or so to keep the temperature around 70 C. 

I don't know which version of Windows you are running, but if it happens to be Windows 7, user files on the primary disk partition are automatically backed up (if the default hasn't been changed) and perhaps your wallet could be restored:

"Windows 7 and certain editions of Windows Vista come with an automatic file and folder backup feature called “Previous Versions” that many PC users don’t seem to know about. Individual data file and folder backups are created by System Restore or by Windows Backup. With the default setting for System Restore, this means monitored files are backed up once a day. To be more precise, records called “shadow copies” are created. These keep track of any changes that have occurred for files and folders.

These shadow copies can’t be accessed directly. To see the previous versions of a file or folder, right-click the object and choose “Restore Previous Versions” from the context menu.  A dialog listing the previous versions will then open. An example for a folder called “PDFs” is shown in the figure below. Only dates when the file or folder had changes will be shown. There are three buttons that allow for various operations with a selected previous version. Clicking the button "Open" will display a selected entry. Clicking "Copy" will allow you to create a copy of a particular version and save it in a different location. Clicking "Restore" will replace the present file or folder contents with those of the selected version."

note:  if the file to be restored is missing and you know the name and location, it is possible to create a dummy file in the same location with the correct name, then right click on it, and choose "Restore Previous Versions".  If there are previous versions saved, one can be selected for restoration.

I didn't know about this until I read it in a Windows newsletter article. 

There once was a miner named Greg,
Whose rigs were straight from New Egg,
  His wife said no whining,
  It's me or the mining,
So down on his knees he did beg.

If you would care to post the recipient bitcoin address, someone can check the blockchain and see if the bitcoins paid for were sent or not.

Second Life and Bitcoins...  I was intrigued to find two exchanges that facilitate trading between bitcoins and lindens (Second Life currency).

My computer is used for many things besides BTC mining and the computer is powered on 24x7 whether mining or not, so I don't allocate 100% of the electricity usage of the computer to bitcoin generation.  It is harder to show a profit on a dedicated rig. 

I've tried a number of different pools and I don't think it makes too much difference which a small miner uses.  Recently I've been experimenting with p2pool.  I don't seem to be making quite as much, but I like the concept. 

What's SLL?


SLL = Second Life Lindens

Lindens is a virtual currency used by Second Life residents.  Virwox and "The Rock Trading Company" are exchanges that, among other things, enable exchanges between bitcoins and lindens. 

-RAM-