Is there a Wii Controller Charger on the market that can plug in via the Wii's USB port?

If not, would it be possble mod a Nyko charger to charge that way? Does the USB port on the Wii give out enough juice to be able to do so?

Funny thing, I've developed a prototype of something similar to this idea a few years ago here on the forums.

It was basically a play n' charge kit-- instead of having the remote just sit on a charger, why not have one in your hands charging via USB like a 360?

Sadly, my schematic's been long gone as well as my prototype. Lost of interest I suppose. But, to answer your question, yes you can make a Nyko charger run via USB, just add the red wire to the red, and black to the black. Nothing else is needed since it does run off the 5v the USB provides.

I would love to have a play n charge cable, much like the Xbox 360 or PS3.

so all I would need to do is splice the wires and it should work? I don't know much about Electricity , and I don't want to have it not work, fry it, or worse, cause a fire.

Also, does the Wii provide power to the USB port in Off/Standby mode?

Yes, it should charge in standby mode (When the light is yellow on the Wii Power button), If the light is red, then no.

As far as splicing, yeah it should work, but I've never tried on a dual charging station before (I've tried only a single). But even at 5v, it isn't anything to cause a fire or something. If you think about it, most devices use this standard. 

If anything, it could just take longer than the normal 8-10 hours  to charge than hooked up to a wall socket since it may be underpowering it a bit. Some docking stations even provide a USB plug in the back, but I'm not sure what yours is like.

If you're still on the fence about this, see if you can ask a mod to move this to the brewery section to see if anyone can help you there and get a second opinion. If all else fails, worse case scenario, you'd only be out a charge cable for your nyko charger.

Here's a quick diagram I made to help you explain what you may be trying to achieve if you'd like:

I got that exact same one pictured from Nyko

Okay, after extensive searching, I found that someone FINALLY stole my idea (which is a good thing, I wanted this to come out years ago! lol)

It's actually fairly cheap too:
http://www.amazon.com/Replacement...

So I guess that'll be a good alternative if you don't wanna hack up your Nyko charger. Hope that helps!

I had some that did this
They were made by ICON
and Unlike what you showed above that is USB to funny round plug

Mine used USB A -> Mini Usb
So the cables were easily replacable if needed.

I built a base for them that had a USB HUB inside
They worked well for ab out 2 years then died sadly.

I recently got some Energizer ones that use a pad where in you plase them on the pad and charge.