Seen reference to drift anchors and drift socks.
Be careful with them. Some rivers have more current than others, and most lakes have none. In those swift current areas, I have seen guys drifting with either the anchor out or the sock out, and either/or catch something on the bottom, or in the river, like a log jam or rock pile or whatever. When this happens the boat stops and stops quick. I've seen guys fall out of the boat. Seen a guy have his drift sock in the back and it hung up on a rock pile, and of course most Jons aren't designed to fight 10mph current with the stern, and it took on water and went down before he could get the line cut. In that river, you don't have long before yout get too cold to swim even in the middle of the summer.
Thus, if you're going to use one of these devices, keep a SHARP knife handy, and use a rope (not a cable or chain) so that if you get into the situation, you can cut the line quickly and easily.
This past summer I seen a guy in North Arkansas using a piece of chain to drift on the White River, and the chain got hung up. Boat stopped and was turned sideways to the current. Luckily the ol boy got it unstuck before it took on much water.