These bright white LED panels are the same sort used in backlights for LCD displays, usually tucked just behind the display. The LEDs are encased in acrylic to produce a beautifully even light, and there's a foil reflector behind to maximise the light bounced forward.

Use gels or even marker pens on the acrylic to change the colour of light produced. Get creative and use these panels in your wearables project; they're much less power-hungry than EL wire or panels and don't need an inverter (although they aren't flexible like EL lights).

Datasheets