I've got my phone out of my pocket at least fifty times a day, usually for insignificant tasks like clearing notifications. But, if Microsoft's new haptic sensory system becomes a reality, I'll be able to keep my phone out of sight but still control it through my pants.
The PocketTouch system, developed by Microsoft Research, employs a custom capacitive sensing grid mounted on the back of a phone to detect multi-touch inputs through fabric—including heavy fleece and jacket pockets. This allows the user to do anything from silence a call to send a text without having to actually pull out the phone. Researchers employed Windows' stroke-recognition engine to interpret a user's various swipes though a wide variety of materials.
To solve the system's primary problem—how to establish the phone's orientation when unseen in a bag or pocket—researchers incorporated an "orientation-defining unlock gesture" that tells the system which way is up. Once calibrated, the sensing grid will work from any angle as long as the inputs are consistent.
There's no word yet on when—or if—this technology will be integrated into future WP7 phones, though I'm more curious as to how this won't pocket dial everybody in my contacts list the first time I throw it in my bag.