Toilets, Sinks, Showers, Tubs and Disposals - Tub faucet drips when toilet is flushed.

I noticed this morning that when the toilet is flushed the bathtub faucet dripped just slightly. Its probably not a big deal but wanted to see if anyone has run into this before. It barely drips maybe just once or twice but it didnt drip unless the toilet was flushed. I turned on the sink faucets to see if the same thing would happen but it only occured when the toilet was flushed. Any ideas on what would cause this? Its a delta faucet and we are on city water.

My kitchen faucet drips when I flush my toilet. What happens is pressure then becomes reduced at the seating of the washer when you have some of the water diverted to some other fixture (such as the toilet, in our cases). When all the water is off in a house, you have full static pressure. But as soon as you open a tap or flush the toilet, you have less pressure elsewhere, to some degree, mostly when 2 or more fixtures share a 1/2 inch line. This principle is similar to how when your refrigerator kicks on, you can have a slight dimming of a light bulb somewheres that is on at the time.