If you shave your head--you might consider this:

If I were a guy and could shave my head:

I would buy one of those ultrasound facial devices with the red led from ebay.  I would make some green tea and put it in a small spray bottle and use it for the wetting agent for the ultrasound.  I would do a 15 minute treatment every day on my shaved head.  You would then get the advantage of both led light and ultrasound.

Here is my research:

http://www.google.com/patents/US20110230793

http://www.livestrong.com/article/288179-the-benefits-of-green-tea-to-hair-growth/

This is the type of device I mean;

http://www.ebay.com/itm/3Mhz-Ultrasonic-Firming-Lifting-LED-Light-Therapy-Care-Skin-Rejuvenation-Device-/171250684919?pt=US_Skin_Care&hash=item27df5613f7

They have all kinds of these types of devices at all different prices.  I would make sure you could use the led and ultrasound at the same time.  I didn't see the information on simultaneous usage on this one, so the best thing to do if you wanted this one, would be to message the seller. The ultrasounds have to be used with a wetting agent, like an ultrasound gel, but some women, when using it for the face, use just water.  Since green tea has all kinds of antioxidant benefits, it would be better than water.  Oil is not used for ultrasound.

I thought of this because I just bought one of these devices for the face.  The ultrasound head on mine is smaller to navigate the face, but for the cranium I would think you would want a bigger one, similar to the one I posted.