5. Brett Murray's The Spear
Those that have been paying attention to the news will remember this one from May 2012.
Following the African National Congress (ANC) condemning Murray's portrayal of South African president Jacob Zuma, two men entered the Goodman Gallery in Johannesburg, defacing the work by painting a red cross over Zuma's face and genitals. They then proceeded to smear black paint all over the canvas, obscuring the image from view.
The attack on the work took place while the ANC undertook legal proceedings for the right to censor the image, bringing much media attention to both the work and its creator.