The act of intentionally causing the banning of a GameFAQs account by posting numerous, usually entertaining, TOS violations. It is usually undertaken as a protest against actions taken by CJayC or a GameFAQs Moderator, but may also be undertaken for other reasons. (From "LUE" + "(sui)cide")
If anyone has archived LUEcides on the Internet, I order and command you to submit them to as many search engines as you can think of.
When people don't want their account on GameFAQS, instead of closing it, they decide to go out in a flash of glory by breaking every rule in the TOS. (such as linking to the Trinity, censor bypasses, etc.) Those who decide to go out in this manner get KOSed, basically they can never use that IP to get an account again. LUE is thought of as anything and everything offensive, so people started using the term LUEcide. Any post containing the LUEcide will automatically be marked.
LUEicide, like it is originially called, is a term most used by people that visit the GameFAQs board "Life, the Universe, and Everything", or simply called "LUE". The "Icide" part at the end of the term LUEicide, stands for suicide, which means killing yourself. A LUEicide is killing not yourself, but your GameFAQs account on LUE, which became a very populair way of getting rid of your account if you don't want it anymore.