THE BOTTOMLESS PIT

Some nutty physicist has figured out how long it would take you to fall through the Earth if you could drill a hole through the entire planet and jump in. The scientific details are extraordinarily dull (and can be read at Hyperphysics.phy-astr.gsu.edu/hbase/mechanics/earthole.html), but the bottom line is that the journey would take a little over 42 minutes, at which point you would fall back into the hole for an oscillating journey which would last forever.