Self cover buttons
I love self cover buttons and covered dozens and dozens for my sewing book 'Torie Jayne's Stylish Home Sewing'. I love how they can add interest to a whole bunch of projects by covering them in contrasting coloured and printed fabric...
Covered buttons are basically fabric-covered forms with a separate back piece that secures the fabric over the knob.
I personally prefer using the white nylon variety of self cover buttons rather than the metal versions when they are small.
They are available from all good sewing and haberdashery shops.