Atmel has recently announced new single cycle 8051 microcontroller family. Which gives a through put of 20 miilion instruction per second.

Here is some extract of the same for Atmel site

Atmel's New Single-Cycle 8051 Core Provides Big Performance Boost and Low Power

12 Times Faster than the Standard 8051 Core Power Consumption Reduced by 85%

Nantes, France, March 8, 2005 . . . Atmel® Corporation (Nasdaq: ATML), a global leader in the development and fabrication of advanced semiconductor solutions, announced today the availability of its new AT89LP family, based on a Single-Cycle 8051 Core. Twelve times faster than the standard 8051 core, this new family extends the existing range of 8051 Flash microcontrollers.

These new devices are optimized for applications that require low power consumption and at the same time high performance at low cost. A wide operating voltage range of 2.0V to 5.5V is offered to accommodate power management, white goods and battery-operated applications.

The AT89LP CPU requires only one clock cycle for every byte fetch, whereas the classic 8051 CPU requires 12 clock cycles for every byte fetch. The AT89LP core is capable of 20 MIPS throughput at 20 MHz clock frequency. In comparison, the classic 8051 architecture delivers less than 2 MIPS at 20 MHz. Conversely, at the same MIPS throughput as the classic 8051, the new AT89LP core runs at a much lower clock frequency, thereby reducing power consumption by 85%.

The AT89LP family consists of devices with 2 to 64 Kbytes of in-system programmable Flash memory, and is available in a variety of pin options, from 14, 20, 28 and 44. They include on-chip DataFlash®, 10-bit ADC, analog comparator, pulse width modulators, programmable watchdog timer, enhanced UART, internal RC oscillator, functions which are ideally suited for power management, motor control and industrial control applications.

The first two devices of the family are the AT89LP2052 and AT89LP4052. Housed in 20-pin PDIP, TSSOP, SOIC packages, they feature 2 Kbytes and 4 Kbytes of Flash code memory, respectively. They are pin-compatible with the existing AT89C2051 and AT89C4051. Samples are available now with production in 2Q05. Pricing for 10,000 units is $0.85 for the AT89LP2052 and $0.99 for the AT89LP4052. In-system Programming of these devices is supported by the AT89ISP programmer, which has a retail price of $25.