Basically you need to drive right up to the pill, turn 90 degrees and start moving as slowly as possible (no auto-slowdown, remember?). The pill will shoot parallel to your movement instead of shooting you. You can also (if the lag is agreeable) start and stop, timing your movements with the pill's bullets. This technique can also be used to decoy pills, and to kill pills without using any bullets:
This is quite difficult to do, especially with lag (you must come in at a steep angle and time and steer your tank perfectly), and is therefore not very practical, but it is a lot of fun so I recommend trying it out.