Here's what we use. It works great, is easy to use, and eliminates a flasher on the line.

Get a Fish Flash by Big Al's. It's a triangular flasher with bent corners. Rather than make big, sweeping circles, it just goes along straight, while rotating in the water.

Ok, take your Fish Flash and clip it directly to the downrigger ball or cable just above the ball. Run it about 6 feet back.

Drop the ball aboout 4 feet and clip your release to the cable. Run your spoon, or whatever lure you're using about 10 feet back. This should put it about 4 feet behind the Fish Flash and 4 feet above it. This technique could be done using regular Hot Spot flahsers, but due to the large circles it makes, you have to put your lure about 10 feet above it at the minimum and even then, you may get some tangles. The Fish Flash is the way to go.

Now, when fish sees the Fish Flash and it attracts them, they get behind it and the lure is right above them. Since fish see up, it puts the lure in a perfect position to induce a strike. Not only is this technique very effective, it also eliminates the need to have any kind of flasher on the main line so you're just fighting the fish.