Free Elixir (kinda)

This isn’t as great of a trick, but you can use it to make some extra elixir if you are available at the time.

When a research is about to finish in your laboratory, fill up your barracks to train whatever troop you are researching the upgrade on. 

For instance, I was upgrading from level 3 giants to level 4 giants.  Level 3 giants cost 1,500 elixir and level 4 giants cost 2,000 elixir.  I had about 180 capacity in all of my barracks.  So I “bought” 36 giants at the cost of 54,000 elixir (36 x 1,500).  After the research was completed, the giants I had “bought” became level 4 and worth 2,000 elixir each.  I cancelled the training and received 72,000 elixir (36 x 2,000).  It’s 18,000 free elixir.  Like I said, not great, but it’s better than nothing.