ZS100 Filter Adapter exists: Panasonic Compact Camera Talk Forum: Digital Photography Review
Camera Accessories Bundle Set For Panasonic Lumix DMC TZ100, ZS100 camera including ND2 ND4 ND8 Filters set, Adapter Ring, Black filter pouch : Amazon.com.au: Electronics
Panasonic LUMIX ZS100 1-inch 20.1-Megapixel Sensor Point and Shoot Digital Camera with LEICA DC 10X Lens DMC-ZS100K Black DMC-ZS100K - Best Buy