Chrome has an awesome Task Manager that allows you to end unresponsive tabs. Sometimes you accidentally create an infinite loop or something and a tab becomes unresponsive to clicks. You frustratingly click that 'X' on the tab, but nothing happens. Your computer begins to slow and your heart melts...
Window -> Task Manager
Select your process, click 'End Process', and kick it to the curb!
P.S. - There's an easter egg in the columns.