"Resistentialism" is a word made up by humorist Paul Jennings as a blend of "res" (Latin for "thing"), "resist", and "existentialism," to describe "the theory that inanimate objects demonstrate hostile behavior against us."

In his essay "Report on Resistentialism," Jennings claimed the idea originated in a French saying, "Les choses sont contre nous" (Things are against us) and a thinker called Pierre-Marie Ventre: "In the Resistentialist cosmology that is now the intellectual rage of Paris Ventre offers us a grand vision of the Universe as One Thing - the Ultimate Thing (Dernière Chose). And it is against us." The spoof on existentialism becomes even clearer when Jennings talks about how Ventre's play, "Puits Clos, concerns three old men who walk ceaselessly round the bottom of a well. There are also some bricks in the well. These symbolize Things, and all the old men hate the bricks as much as they do each other." -- a clear reference to Jean-Paul Sartre's play Huis Clos and its three main characters trapped together. Another Resistentialist play Jennings talks about calls all its human characters "Poussés" (in English, "Pushed-Arounds").

This war of inanimate objects idea rings true with many people and has done so for centuries; a New York Times article points out such instances as:

In his ''Ode (Inscribed to W. H. Channing)'' (1846), Ralph Waldo Emerson saw the resistentialist writing on the wall and proclaimed that ''Things are in the saddle,/And ride mankind.'' In his autobiography, published posthumously in 1924, Mark Twain relates an anecdote about a recalcitrant burglar alarm in his ornate mansion in Hartford. It ''led a gay and careless life, and had no principles,'' he says. ''We quickly found out that it was fooling us and that it was buzzing its bloodcurdling alarm merely for its own amusement.''
Indeed, Anu Garg, maintainer of the A.Word.A.Day mailing list noted in his entry for resistentialism that "As if to prove the point, my normally robust DSL Internet connection went bust for two hours just as I was writing this. I'm not making this up." Word Spy says the word has gained popularity on its own (no longer as just the spoof on existentialism) in the last five years as more people deal with computers and the Internet, which can certainly seem to be more actively acting to interfere with what humans want to do than other objects can manage.

Sources:
http://wordsmith.org/words/resistentialism.html
http://www.wordspy.com/words/resistentialism.asp
http://www.resistentialism.net/
http://www31.brinkster.com/yewtree/resources/resistentialism.htm
http://www.nytimes.com/2003/09/21/magazine/21ONLANGUAGE.html