how could i make a homemade vibrater?

A electric toothbrush has been known to make a small personal one!

Homemade Vibrater

Buy a small electric sander at a hardware store. Make sure the sandpaper is off. It's usually coated with a soft black rubber coating. Plug it in. Turn it on....carefully message all the delicate cracks and crevices, applying moisturizer and lubricants where necessary. If you like privacy close the door. If you like to be watched leave the door open or just stand by the front window with the shade up so you can be watched. The electric sander usually has several speed settings for you vibrating comfort. Be sure to wash it when you are finished...there's nothing worse than a dirty vibrator!

I don't know what you plan on vibrating, but you can try using a reciprocating saw with a banana shaped attachment in place of the blade. I'm guessing it would be an interesting way to make a milkshake.

depends on what you want to vibrate.

a battery operated tooth brush.