The Book Pertaining to the Turmoil and Portents of the Last Hour (Kitab Al-Fitan wa Ashrat As-Sa`ah)
Muslim :: Book 41 : Hadith 7044
This hadith has been reported by Sahl b. Sa'd that he heard Allah's Messenger (may peace be upon him) as saying: I and the Last Hour are (close to each other) like this (and he, in order to explain it) pointed (by joining his) forefinger, (one) next to the thumb and the middle finger (together).