You shouldn't run this program in a loop. I added a note to the readme, thanks for the tip.

I was bored today, so I wrote a java application to find arbitrage deals based on the market data from http://bitcoincharts.com/
It's a console application printing out an arbitrage deal table similar to http://bitcoin-analytics.com/

Example output (the forum destroys the formatting):
+----------------------------------------------------+-----------+--------+-------+--------+----------+-------+-----------+--------+---------+-------+-------+
|                                                    |bitcurexEUR|btcdeEUR|btceEUR|crytrEUR|intrsngEUR|justEUR|localbtcEUR|mtgoxEUR|rippleEUR|rockEUR|vcxEUR |
+----------------------------------------------------+-----------+--------+-------+--------+----------+-------+-----------+--------+---------+-------+-------+
|bitcurexEUR, ask: 609.0EUR, bid: 595.0EUR           |-2,3%      |-2,13%  |-5,24% |-3,28%  |-12,97%   |-2,79% |21,64%     |0,25%   |-88,18%  |-9,69% |-17,08%|
|btcdeEUR, ask: 600.0EUR, bid: 596.0EUR              |-0,83%     |-0,67%  |-3,82% |-1,83%  |-11,67%   |-1,33% |23,46%     |1,75%   |-88%     |-8,33% |-15,83%|
|btceEUR, ask: 588.74897EUR, bid: 577.05901EUR       |1,06%      |1,23%   |-1,99% |0,04%   |-9,98%    |0,55%  |25,82%     |3,7%    |-87,77%  |-6,58% |-14,22%|
|crytrEUR, ask: 887.99999999EUR, bid: 589.00000002EUR|-33%       |-32,88% |-35,02%|-33,67% |-40,32%   |-33,33%|-16,58%    |-31,25% |-91,89%  |-38,06%|-43,13%|
|intrsngEUR, ask: 560.0EUR, bid: 530.0EUR            |6,25%      |6,43%   |3,05%  |5,18%   |-5,36%    |5,71%  |32,28%     |9,02%   |-87,14%  |-1,79% |-9,82% |
|justEUR, ask: 618.87EUR, bid: 592.0EUR              |-3,86%     |-3,7%   |-6,76% |-4,83%  |-14,36%   |-4,34% |19,7%      |-1,35%  |-88,37%  |-11,13%|-18,4% |
|localbtcEUR, ask: 310.8EUR, bid: 740.78EUR          |91,44%     |91,76%  |85,67% |89,51%  |70,53%    |90,48% |138,35%    |96,44%  |-76,83%  |76,96% |62,48% |
|mtgoxEUR, ask: 618.993EUR, bid: 610.52EUR           |-3,88%     |-3,71%  |-6,77% |-4,85%  |-14,38%   |-4,36% |19,68%     |-1,37%  |-88,37%  |-11,15%|-18,42%|
|rippleEUR, ask: 618.88EUR, bid: 71.99999999EUR      |-3,86%     |-3,7%   |-6,76% |-4,83%  |-14,36%   |-4,34% |19,7%      |-1,35%  |-88,37%  |-11,13%|-18,4% |
|rockEUR, ask: 599.0EUR, bid: 550.0EUR               |-0,67%     |-0,5%   |-3,66% |-1,67%  |-11,52%   |-1,17% |23,67%     |1,92%   |-87,98%  |-8,18% |-15,69%|
|vcxEUR, ask: 600.0EUR, bid: 505.001EUR              |-0,83%     |-0,67%  |-3,82% |-1,83%  |-11,67%   |-1,33% |23,46%     |1,75%   |-88%     |-8,33% |-15,83%|
+----------------------------------------------------+-----------+--------+-------+--------+----------+-------+-----------+--------+---------+-------+-------+

Read it this way: You buy from the left hand market to the ask price and sell it on the header-list market to the bid price.


Feel free to use, fork, extend:

https://bitbucket.org/fuchs82/bitcoin-arb

Happy arbitrage trading ;-)
Fuchs82

--
Donations: 171B7YyhB1Na37BE8aScEct8R2ojxC8PJG

I had the same issue and opened a support ticket. I got a very fast reply, saying this can happen due to server outage. All loss will be compensated automatically within 24h.

I saw my GHS going up above my bought value for some time. So in average I had my correct value. This already happended two times and it's good to see that the compensation works.