Should be easy, I want only one object not to cast shadows.
One way is to have the object on a different layer from other objects, to have it’s own lamp, and for that lamp set to not cast shadows. There are probably better ways.
The lamps on the original layer need to be set to This Layer Only
That seems terribly inefficient… Don’t tell me they don’t actually have a “Don’t cast shadows” thing for me to toggle?
In the material panel select the material you’ll be using for the object you want to cast no shadows.
In the option panel uncheck traceable and that should do it.
cheers
I didn’t know that (obviously). Thanks.
Thanks, you two have been extremely helpful, considering the site.
Haha, no problem, I’m still learning blender myself, but I’ve been doing 3D as a hobby for 14 years.
Took me a little while to find the option myself testing settings and doing quick renders XD
To make things even more confusing, if you are using buffer shadows (the default setting for spot lights), in the material options, there is another checkbox that says “cast buffer shadows” deselect it also
That only applies when you’re not ray tracing correct?
No, buffer shadows and ray traced shadows can be cast simultaneously.
Ah cool, I learned something new. 
If you uncheck traceble, it won’t show up in reflections either.
A buffer-shadow is a cheap, approximate (but usually quite good-enough) shadow. A ray-traced shadow is precise but expensive. They are two separate things.
A “shadow-only spotlight” is another thing: a spotlight that casts no light at all, but does make shadows. (This probably being the handiest trick in the your magic toolbox …)