The Sensor Film Kit is a great new way to make custom-sized sensors out of force sensitive material. This kit includes one piece of black plastic sensor film (it's thicker and more durable than Velostat but similar in function), two pieces of heavy aluminum foil, and two pieces of clear adhesive polyester film. The sensor film is super durable and changes its electrical resistance when force is applied. It's a lot like Velostat but a bit more responsive. The aluminum foil is for electrodes and the clear adhesive polyester film is given to keep the sensors together. It's a great way to make a FSR of any size for your microcontroller project.
There's more info on the Sensor Film Kit site including easy instructions on how to make a basic sensor. They also have a bunch of examples of what you can do with the kit.
This is the Small Sensor Film Kit so it does not include alligator clips.
- Each Sheet is 101.6mm x 152.4mm / 4" x 6"
- Thickness of Sensor: 0.5mm / 0.02"
DIY Sensor Film Kit - 4x6 Small Kit 
- Brand: Adafruit
- Product Code: ADA-1917
- Reward Points: 21
- Availability: 5
- Ex Tax: £21.95
- Price in reward points: 300