The system I am in is about to go into expansion, so there are a tonne of missions that ask me to find the lost Encrypted Expansion Data. These are quite lucrative. Here is how it works.
You go to the system where the data was lost, and hit your Advanced Discovery Scanner (I think it works with the other Discovery scanners, or you can drop in and scan the nav beacon). It will tell you to look in the vicinity of a particular planet. Head there, find the USS that will be reported as your mission target. Drop in, collect the containers and voilà! Easy money.
It took Dawg and I a few minutes a couple of nights ago how this works, but it was quite easy and the pay was good. It also gives you ++ on rep and influence.
Well, last night I did a few more, And the ones that were above my rank, they were a little rough. Had a wing of Four drop in and pick up some of the data before I could, and they were all wanted. Then they open fire. I did a Code 39 and got away. I flew around for a few minutes and another mission target USS popped up and I was able to complete the mission before the wing showed up again. Cashed in and took another couple. It was a wing of a Cobra, Eagle, and 2 sidewinders, all expert or better. Same names both times, so they were hunting me

The next one, I got the cannisters and then got an update to the mission that there were now ships hunting for me, and I would get a bonus for each ship that I destroyed (A total of 4 targets). Cool. First up, Master FAS. I submitted when the target (was named in the update) interdicted me. My little Combat A Rated Engineered modded DBS kicked some ass. But if the Cops hadn't showed up, I would have been toast. Got away with 34% hull. I decided to turn in the mission, but there was a second name in the mission on the transaction tab, but I was not in any shape to get them too.
If you can find these missions, and have good rep with the faction, it can be a good way to make some cash and get more rep for Ranking. Combined with the Expansion Courier missions, you can make a couple of million in about 20 minutes and all you need is 8-16 tonnes of cargo. Not a Tun or Robigo Replacement, but much better than most normal ways.