Top500©: Top 5 Supercomputers as of November 2011					http://www.top500.org/
Current (no changes from 6/2011)	1	2	3	4	5
Last January (2011)	1	2	3	4	4
Computer	K Computer	Tianhe-1A	Jaguar	Nebulae	Tsubame 2.0
Vendor	Fujitsu	NUDT	Cray	Dawning (Voltaire/IBM)	Hewlett Packard
Maximum Speed	8.16 pf	2.57 pf	1.759 pf	1.271 pf	1.19 pf
Theoretical Speed	8.77 pf	4.70 pf	2.331 pf	2.984 pf	2.29 pf
Country	Japan	China	USA	China	Japan
# of Cores	548,352	186,368	224,162	120,640	73,278
Who runs it	RIKEN Advanced Institute for Computational Science (AICS)	Chinese National University of Defense Technology (NUDT)	Oak Ridge National Laboratory	National Supercomputing Centre in Shenzhen (NSCS)	Tokyo Institute of Technology
Location	Wako, Japan	Changsha, Hunan, China	Oak Ridge, Tennessee, USA	Shenzhen, Guangdong, China	Tokyo, Japan
Projects	Atmospheric phenomena	Petroleum exploration	Open scientific research in		Computational modeling and
	Real-time earthquake & tsunami simulations	Aircraft simulation	nanotechnology, biological		simulations
		Available to international clients	systems, energy, etc.		Open research for all students
	(Mostly earth science, material science				at Tokyo Institute of Technology
	engineering & physics sciences.)				- even undergraduates
	Note: Won't enter service until 2012
Website	http://www.aics.riken.jp/index_e.html	http://english.nudt.edu.cn/index.asp	http://www.csm.ornl.gov/	http://english.siat.cas.cn/	http://www.gsic.titech.ac.jp/en
The next Top500 winner will most likely be Sequoia, expected to run at 20 petaflops.  It was originally tracked to win in June, 2011, however has been delayed due to budget woes.  It is being built for the National Nuclear Security Administration (NNSA) in Los Alamos, Sandia and Lawrence Livermore National Laboratories for “weapons’ science calculations necessary to build more accurate physical models. This work is a cornerstone of NNSA’s Stockpile Stewardship program to ensure the safety, security and reliability of the U.S. nuclear weapons stockpile today and into the future without underground testing.”  To put 20 Petaflops into perspective, “if each of the 6.7 billion people on earth had a hand calculator and worked together on a calculation 24 hours per day, 365 days a year, it would take 320 years to do what Sequoia will do in one hour. It will have 1.6 petabytes of memory, 96 racks, 98,304 compute nodes, and 1.6 million cores.1
The NNSA: Established by Congress in 2000, NNSA is a semi-autonomous agency within the U.S. Department of Energy responsible for enhancing national security through the military application of nuclear science in the nation’s national security enterprise. NNSA maintains and enhances the safety, security, reliability, and performance of the U.S. nuclear weapons stockpile without nuclear testing; reduces the global danger from weapons of mass destruction; provides the U.S. Navy with safe and effective nuclear propulsion; and responds to nuclear and radiological emergencies in the U.S. and abroad.  See http://nnsa.energy.gov/.
The expectation, based on development of processor technology, is that the first exascale system may arrive around 2018.  An exaflop is a million trillion calculations per second, or a quintillion, and is a thousand times faster than a petaflop. The development of an exascale system is estimated to happen in the 2018-2020 time frame, but it is also contingent on the development of software systems that can utilize what may be 100 million cores.  from ComputerWorld, http://www.computerworld.com/s/article/9209918/Obama_sets_126M_for_next_gen_supercomputing
1  NNSA awards IBM contract to build next generation supercomputer, February 3, 200
https://www.llnl.gov/news/newsreleases/2009/NR-09-02-01.html