Would it also be possible to add a parameter for avatars to have clocks and watches, even on quests? Or maybe a new shader that would utilize this, that would be whitelisted? I'd imagine it would use a float... or multiple integers? Just an idea I had...

It looks like this is in! https://creators.vrchat.com/worlds/udon/vrc-graphics/vrchat-shader-globals/

Although it is still currently possible to pass in the time yourself through Material.SetFloat and so on. Every frame? You can do it in Update(). If they release Shader functions later too, you can implement that SetGlobalFloat code yourself as well (switch MonoBehavior to UdonBehavior). I'm not quite sure yet if they actually exposed any time code yet; if not, that's really the only thing they'd have to do at this point. Expose time data to scripts, and people can pass that data to their shaders themselves (as I said, passing that data to a shader is already possible, as long as we have that data to pass)

I believe a better title for this post would be:

Expose Shader methods, and expose date time data to scripts

I need the api getting datetime of a local PC clock, for a shader, too.

that would be sooo helpful

I would really enjoy this or something like it. I've searched around the official discord, read some of the conversations on the topic of clocks and time in the Metaverse so far, and the desire for this functionality in one form or another seems obvious enough to me.

Web Panels were a great way to deliver this functionality, and then some, but unfortunately they were insecure and may never be secure in the scope of VR Chat, in my mildly-educated opinion.

This seems like a much easier way to secure the desired functionality of real-time clocks in worlds and on avatars.

Small detail; but something that could be nice to have on avatars

Yes. Pleaseeeee.