This watch is exactly what I was looking for: analog, small with a thin band, simple/inconspicuous, water-resistant and backlit-- and still not too childish.  It's a pretty hardy thing and the backlight is pleasantly green.  The face is barely an inch in diameter, and the whole band is about 9 inches long, so maximum wrist circumference is 8 inches (minimum 6 inches).

For those of us restricted to hypoallergenic watches, it's not *all* plastic: the back of the movement is brushed stainless steel.  But I have a nickel allergy and the steel is a high enough grade that it doesn't irritate my skin in the slightest.

And all for under $20!