Haunted Flourescents?

Factual Questions
1

My bedroom is illuminated by a pair of flourescent bulbs several years old…they are prone to flicker and dim if additional load is placed on the circuit, such as if the air conditioner is running.

I also have a flourescent flashlight powered by a rechargeable battery…part of a cordless power tool kit.

In any case, when I have the room’s flourescents on and also click on the flourescent flashlight, the room’s bulbs dim. I click off the flashlight, and the room’s bulbs come back on full strength.
What strange electromagnetic fields are interacting to create this haunted flourescent phenomena?

2

Probably noise from the portable’s ballast. Those little handheld fluoros run an inverter at several tens of kHz, and the cheaper ones typically emit a lot of electrical noise–try turning one on near an AM radio. Most likely something in the room light’s circuit, such as the ballast, is being interfered with.