What was the most Powerful Hurrican, Cyclon or Typoon ever recorded?

Photo Credit: Wikipedia: Hurricane Rita
in the Gulf of Mexico on September 21,
2005.

As Rita comes ashore we keep hearing that it is the third most powerful Atlantic Hurricane recorded. I got to thinking. What was the most Powerful Hurricane, Cyclone or Typhoon ever recorded?

I mean looking at Wikipedia they list the Labor Day storm of 1935 as having the lowest barometric pressure at landfall on N. America at 892 mbar (hPa). Katrina had 918 mbar (hPa) at landfall and God only knows what Rita will be as it comes ashore.

But my question is, what is the most powerful storm? And after some research I found Super Typhoon Tip in 1979. This was a truly Huge storm with tropical force winds extending out 675 miles. It had sustained winds of 190 mph and central pressure at 870 mbar (hPa), the lowest barometric pressure ever recorded in a tropical cyclone.

To give an illustration of its size Wikipedia gave this:

...if a similar-sized hurricane hit south Florida directly, tropical storm force winds would be felt as far north as Charlotte, North Carolina and as far south as Merida, Mexico and Kingston, Jamaica

Luckily it weakened by the time it made landfall in Japan, but nonetheless caused significant damage. Tip cost the agricultural and fishing industries of Japan millions of dollars in damage. There were 68 deaths from Tip. Hopefully Rita will weaken some more before it makes landfall also.