Wikipedia's list of unusual articles is a good place to lose a few hours that you don't have to lose. I'm fond of Arbre du Ténéré, an acacia in the Sahara that was the only living tree in 400 kilometers until it got hit by a drunken Libyan truck driver. Also Ferdinandea, a seamount that rose above the waves after a volcanic eruption in 1831 and was the subject of a four-way territorial dispute until it sank again the next year, then was mistaken for a Libyan submarine and bombed by the U.S. Air Force. (Take that, tree-killers!) And the Phantom time hypothesis, which holds that the years 614 through 911 A.D. are a myth.
One that's been on my watchlist for a while now is a linguistic curiosity, the sentence "Buffalo buffalo Buffalo buffalo buffalo buffalo Buffalo buffalo." -- which carries a secondary risk of getting lost in the archives of the LINGUIST list. "Unlike American teenage postposed 'not', Australian postposed 'but' seems to form an intonational unit with the preceding material in the sentence." I love that sentence. Not just that it exists, but that it's a serious hypothesis.
I have an icon that combines skeletons and geekiness. Perfect.