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I didn't like that the GlowBowl would only stay lit for around 40 seconds, so I lengthened this to around 90 seconds by replacing C13, an 0805 surface-mount capacitor. (The length of the "motion detected" signal, and therefore the length of time the LED stays lit, is proportional to C13's value; the capacitor that came factory-installed in mine was 10nF.) I've attached a photo showing the circuit board inside the GlowBowl. The device contains a Microchip PIC16F1503 microcontroller which uses PWM to control the brightness of 3 LEDs. Light and motion are detected with a CdS photoresistor and a PIR sensor handled by a BISS0001 PIR-controller IC, which uses the above-mentioned capacitor to time its output pulses. There is a 5-pin ICSP header on the circuit board, and the microcontroller is neither write-protected nor read-protected, so it can be reprogrammed (I was able to read its code and reprogram it with a PICkit 3). Someone could reprogram the device to, for instance, do smoother color transitions, or have different brightness levels, if they were so inclined. By the way, current consumption with 4.5V provided to the battery leads is 1.2 mA when the LEDs are off, 8.2 mA when glowing white at the lowest brightness setting, and 36.5 mA when glowing white at the highest brightness setting. (Single-LED and two-LED colors draw less current than white does.) Assuming 3000 mAh for 3 AAA batteries, if the unit never turns on, Digi-Key's Battery Life Calculator estimates a lifetime of 1750 hours, which is 72 days.