It's very handy to use the mission computer bug if you have a bunch of escorts and you've just sold all your cargo. It's much faster to fire your escorts by doing this than by hailing each one and telling them to go. Plus it costs a lot less since you don't have the added day from taking off.
The most useful money making cheat I've ever used (this is most useful in Star Wars which is fighter intensive and where tractor beams are common) is to steal fighters without even having the matching bay. All you do is fight a ship that has fighters. Disable the fighters and the ship, then pull the ship around with the tractor beam (you have to move fairly slowly but you can pull it). Pull the ship over the fighters and the fighters will disappear into their mothership. Now the ship has fighters in the bay, so if you board it, there's a chance that the fighters will show up in the "ammo" part of the boarding screen. Since fighters are weightless and since boarding lets you take unlimited ammo from a ship regardless of the maximum amount, you can easily pick up a few million credits' worth of fighters by just fighting one or two pirate Kestrels, or a Rebel or Confed Cruiser. Even if you can't sell the fighters it's okay because they'll contribute to the trade-in value of your ship.
One fun thing I would do (this was less of a cheat than a money-making endeavor) was to buy industrial supplies at Sirgil Starport when they were at the "lowest" cost of 5 credits per ton. Then I'd keep landing and taking off until the price went up to the "highest" cost of 440 credits per ton. That's about 17 000 profit if you're in a scoutship, so I'd eventually get enough money to hire light freighters and fill their cargo bays with the stuff. It was fun to try to see how long I could hold out, waiting for the price to change and all the while paying my escorts to stick around. Almost 400 000 profit if I had six light freighters all filled up, and that's not counting my own ship.
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Luca Rescigno
How are you gentlemen!! All your base are belong to us. You are on the way to destruction. You have no chance to survive make your time. HA HA HA HA