1357% profit

I was selling mission loot this morning, and as I'm going through all the items in my hangar, I was taking a look at buy and sell prices, see if anything was worth trading. And sure enough, I found quite a few.

+-----------------------------------------------+--------+---------+----------+
|           Item                                |  Buy   |  Sell   | Profit % |
+-----------------------------------------------+--------+---------+----------+
| Alven Surface Targetting Annex                |  8,500 | 123,864 | 1,357.2% |
| Burned out logic circuit                      | 16,000 |  16,025 |     0.2% |
| 100mm Reinforced Crystalline Carbonide Plates | 21,002 |  34,890 |    66.1% |
| Explosive Deflection Amplifier                | 50,500 | 109,990 |   117.8% |

+-----------------------------------------------+--------+---------+----------+

A few notes about the above:

• All items were sold on Jita, but the method of purchase varied
• Someone was selling 5 Targetting Annex at another station in the Jita system for 8500 ISK. I quickly bought them and flew over to pick them up. 650,000 ISK, not bad for about two minutes of work (I couldn't sell anything else on Jita anyway, I didn't have any order slots left).
• Someone was selling the Burned Out Logic Circuits for 16,000, while another player was buying them at 16,025, at the same station. Since you don't incur many fees by buying/selling retail, I scooped them all up. 0.2% profit may not seem like much, and normally I wouldn't bother. But this was an instant retail trade, and the volume was interesting enough (4961). It's only 124k ISK, but since it only took me 10-15 seconds, that's really like 29.5m ISK/hour.

These are abnormalities in the market, so you can't count on them to make ISK consistently. But you should be on the look out for them, since the can fatten your wallet a bit, with almost no additional effort on your part.