Science Vessel Eraser
In the Terran vs. Zerg match-up, a Terran player can have a large cloud of Science Vessels. The Eraser trick is a great way to utilize your Science Vessels by using the Irradiate ability in a creative way. The trick takes advantage of the splash damage Irradiate does, and enables you to kill many units with relatively few Irradiates, or decimate your opponent's Drone line in a matter of seconds.
Doing the Eraser trick is very easy, you only need two or more Science Vessels with Irradiate researched. To do the trick, simply have your two Science Vessels irradiate each other, and fly them over or near the units you wish to kill. Since Science Vessels are not biological units, Irradiate has no effect on them; however, Irradiate's splash damage hurts surrounding biological units.
This technique is most commonly used against:
The technique can also be used as a limited defense against Scourge, as the Scourge will take damage from the splash. 2-3 irradiated Vessels with respective micro are hard to kill with Scourge until radiation wears off.
You can also use a Dropship or some other air unit for the Eraser trick, but that is less common because you mostly have many Vessels.
The Science Vessels can also Defensive Matrix each other, to minimize damage if there are Hydras or Spore Colonies in Zerg base.
The technique is countered by Drone slides or researching Burrow. Irradiate deals no splash damage to burrowed units.