Competitive baseline was the Sony TZ series.
.16" to .76" thickness. You could mail it in a large envelope.
13.3" widescreen display with LED backlight. Magnetic latch. iSight included.
Macbook-style keyboard with ambient light sensor (if this is what I have seen on Panasonic Toughbooks - it is slick).
80Gb 1.8" HDD or 64GB SSD.
1.6GHz or 1.8GHz Core 2 Duo.