This conductive pressure sensitive material (also known as "Velostat" or "Linqstat") is a good addition for your wearable/sensor hacking toolkit. It is pressure-sensitive, by squeezing, it will reduce the resistance. This make it good choice for making flexible sensors. 

It is also much less expensive than off-the-shelf pressure or bend sensors too. Each order comes with  28cm x 28cm piece. You may cut your sheet into many pieces and use each of them alone.

Dimensions: 280mm x 280mm

Thickness: 0.2mm

Weight: 18.66g

Temperature Limits : -45°C to 65°C (-50°F to 150°F)

Heat Sealable: Yes

 Check this instructable for pressure sensor sheet tutorial