The Times have published their ranking of the top universities around the world showing Harvard on top, with Cal Tech second and MIT third. The highest non-US universities are UK rivals Cambridge and Oxford with suspiciously equal scores in place 6. Imperial is not far behind in place 9. The best non-anglophone placing is Zürich in 15.
When ranked by research output alone Berkeley jumps to first place and Imperial slips ahead of Cambridge and Oxford. The university of Tokyo also makes the top ten as the highest rank outside the English-speaking world.
There is a separate ranking for citation index which shows some wild results including Alexandria University in Egypt jumping from position 147 overall to 4th place. You can form your own point of view on whether this reflects a real achievement or merely indicates how unreliable citation indices are.