Light Emitting Diodes (LEDs) are the new glitter.  

My Stabby Valentine is a simple no-sew textile Valentine with a surprise. A layered switch is created with conductive fabric, insulating felt, an LED, a 3V battery. Activate the Valentine by stabbing it with a metal straight pin. For more How to DIY eTextiles, soft circuits, and wearable computing please visit the eTextile Lounge youTube channel. Instructable