T-Theremin is an Android application that allows the user to create sounds and sound effects similar to those made by an actual theremin. Popularized by music and sci-fi movie sound effects in the 50's and 60's (think of 'Good Vibrations' by The Beach Boys), the theremin creates an eerie, futuristic sounds based on the proximity, location, and movement of the player's hands relative to the instrument. In a similar manner, the T-Theremin uses the Android's orientation/tilt sensors to modulate the frequency of an auto-generated tone. Tilting the top of the device upward creates a higher-frequency tone, while tilting the top of the device downward results in a lower-frequency tone. A thumb-controlled horizontal slider on the device can also be used to vary a tremolo effect from 0 to 10 cycles per second.