Are there any lasers with a separate on switch
like you'd find on the newer Delta saw, for example, that don't require
the
blade to be spinning first?

Yes, there is the Laserkerf laser.
Here is a detailed review:
http://www.onlinetoolreviews.com/reviews/laserkerf.htm

Hope that helps!

--
Regards,

Dean Bielanowski
Editor,
Online Tool Reviews
http://www.onlinetoolreviews.com
Over 70 woodworking product reviews online!
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