An extremely popular and reasonably extensive timeline made by Calbear where the Nazis temporarily win the war in Europe - defeating the Soviet Union and laying waste to most of Europe - only to lose overwhelmingly to the British Empire and the United States in 1958. The Nazis devastate almost all the rest of Europe in a fit of rage at their loss.
Hitler decides not to send the Afrika Korps, and he doesn't invade the Balkans either. So, the invasion of Russia doesn't have to be postponed. With the extra resources and time, the Nazi army is dug in in time to survive the winter. When they continue advancing the next spring and take Stalingrad, Stalin falls into a fit of rage and executes almost all his surviving officers - which only worsens things. By spring 1943, Stalin is mysteriously dead, Molotov wins the power struggle, and he seeks terms with Hitler. All of European Russia is surrendered, and Soviet Siberia is forced to pay punitive reparations (including labor battalions.)
Hitler then proceeds to rebuild Europe in his image. The Jews, Poles, Slovaks, and Russians are worked to death or simply killed. Germans colonize Poland. The Wehrmacht itself is disbanded, to be replaced by an SS that promotes on ideological loyalty. Britain and America encircle this disaster area by occupying Vichy North Africa and the Middle East, but they fear any actual invasion would result in destruction.
Then the Nazis decide to launch missiles at America to force it out of the war. Yes, they were that crazy. Of course, it only heats up the war again…
Calbear updates the timeline regularly every Saturday. It's posted here, with tons (yes, tons) of comments. For easier reading, note that .doc files containing all the posts so far have been uploaded a couple times. The definite, comment-less and proofread version of the timeline can be read here.
The timeline has won two Turtledove Awards: