I have personal first hand experience
with classical conditioning.
I used to live in an apartment above a trendy coffee house at the university that I attended. The place was long and narrow, and my roomate and I set up the front of the apartment with couches and television.
The TV that we had was one of those old public school types, that had more connectors on the back than I knew existed, and had obviously been bolted to the top of a rolling cart at some point; this was even more obvious when I noticed the half-torn sticker that warned children not to climb on the cart, lest they be crushed by a heavy object. The source of this monster (weighed in at over 100 pounds) was an old roomate's mother, who worked for a public school in Ohio. Regardless, being the poor college student that I was, having a 25" television for free was awesome.
Of course, there is always a catch. The television was probably late 1970s or early 1980s by the looks of it. It had dials to tune the stations (separate UHF and VHF), and the brightness and volume dials were metal and not automatic in any way shape or form. I did have a cheap cable box attached to the set that did allow me to change channels and turn the monster on and off. However, volume adjustment required a 20 foot trip across the carpeted floor to the volume dial.
Static electricity is perfect for classical conditioning. Across that stretch of carpet, I picked up quite a few electrons and upon touching the volume dial, ZAP! Almost every time. It was so bad, that eventually I would move my arm close to the television and instinctively retract my arm in fear of a static electric shock. It would take me several waves of my arm to eventually touch the side of the metal encased television to ground myself before I could adjust the volume. This happened for a year and a half.
I moved. I brought television monster with me (along with its friends, the ColecoVision and a VCR that I found in the trash but fixed up into a workable device). New house didn't have carpet or static electricity problems. However, my classical conditioning made it that for at least the next 6 months, I couldn't touch the volume dial without instinctively doing the several waves of retracting my arm to ground myself. No matter how conscious I was that I was in no danger of being shocked, I still couldn't touch the dial without going through the ritual.
I got rid of the television years ago. I'm sure if I ever saw it again, however, I'd probably still have a problem with the volume dial.