What is your favourite switching regulator for low current 5V output?

My parameters are as follows: -

Input voltage - nom 12V, looking at range of 10V - 20V
output voltage 5V fixed
output current 10-200mA.
Surface mount, SO-8 or smaller preferred.

The equipment is expected to be powered from a bus most of the time, but at
higher currents a wall wart would be expected as the supply. In most cases
the current draw will be a PIC and a handful of interface chips, with a
couple of LEDs. One alternative use would require pulses of current, but
this would also have a wall wart as the supply, or a large capacitor may be
enough in some instances.

My browsing of manufacturers web sites has turned up the following.

Linear Technology - LTC1174
National Semiconductor - LM5008

Both manufacturers do seem to have other devices that could be alternatives.

Specifically looking for switching regulator rather than linear, with a
minimal external parts count. Both of these chips seem to do this, but
wondering what other discoveries list members have faced with similar low
current draw.

At this stage it is all investigative stuff, and I may yet fall back on a
78L05 or similar linear device, but would prefer to use a switcher as the
source supply from the bus is limited in current. It may even be that the
most efficient in cost/performance is a version of Russell's transistor
circuit, but I am a wee ways away from experimenting yet, and still getting
the "blue sky thinking" part together.

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