John, this
<http://www.coleparmer.com/catalog/product_view.asp?sku=4150050> will
prolly do just what you want.  Mind you, when you add the single
fiber-optic head and a lens it's going to cost you $560 plus
shipping.  Dual head and second lens would be another hundred.  The
diameter of the fiber where the light exits is about 3/16 inch, so
maybe if you use it close enough you wouldn't need the lens.  The
brightness control works on the lamp, so the color temperature varies
with the brightness.  I have a previous version of this lamp with
dual head but without lenses.  It's well made, serious gear,
fan-cooled.  Keep the head-to-base joint lubricated so the aluminum
doesn't freeze together.

If you google for fiber optic illuminator you'll find other possibilities.

Regds,
David

At 09:26 PM 8/31/2008 -0500, John Rodgers wrote:
>Dear Volksbretheren,
>
>I am in need of a gooseneck lamp - halogen bulb or LED - with a focusing
>beam. I do really fine tooling work like what is found on  fine hand

--
David Beierl - Providence RI USA -- http://pws.prserv.net/synergy/Vanagon/
'84 Westy "Dutiful Passage," '85 GL "Poor Relation"