R-evolution GFX has illustrated Cave Johnson's combustible lemon in tribute to Portal 2 and Cave's memorable speech. You can buy the Combustible Lemon T-shirt here.
"Alright, I've been thinking. When life gives you lemons, don't make lemonade – make life take the lemons back! Get mad! I don't want your damn lemons, what am I supposed to do with these? Demand to see life's manager. Make life rue the day it thought it could give Cave Johnson lemons. Do you know who I am? I'm the man who's gonna burn your house down! With the lemons. I'm going to to get my engineers to invent a combustible lemon that burns your house down!"
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