If you make use of public transport (buses, trains, planes, space-craft) you will realise that there are certain things that you should and should not do. There's actually a manual produced by NASA that contains all the dos and don'ts for public transport I believe. One of the lesser known don'ts that deserves to be more widely known concerns the furnishings of the vehicle. You will notice loose pieces of fabric, or dangling wires, or loose beams. Do not attempt to tidy them up or pull them! Here's an example of what will happen if you do.
A few months ago I was on board a plane in Hong Kong bound for London. My job as a delayed passenger takes me to many countries. If an airline, or airport or both is running at a too high-level of efficiency I am instructed to appear and experience lost-luggage, delayed flights and overbooking in order to keep the efficiency within the approved levels (as determined by marketing). I had successfully boarded after spending 15 days sleeping in the airport waiting for my delayed flight to be scheduled (my ticket ensured I was unable to take any other flight without severe punishment).
As I waited on the plan for the remaining passengers to board and stow their luggage I noticed a piece of fabric dangling from the partition. Being a tidy person I tugged the dangling fabric. I freed the fabric and carefully folded it and put it into the seat pocket in front of me. As I settled back into my seat I heard a rather loud crash from behind me followed by a gust of fresh air. I turned around and noticed that the back-part of the aircraft (specifically rows 50-60) had detached itself from the front part and fallen to the ground. Fortunately, the boarding procedures ensured those rows were empty and only my luggage (which I strategically placed in rows 53-55) suffered and was now spreading itself over the entire airfield.
Moments later an irate engineer came up to me and asked me if I had touched anything. I responded that I had not and had only tidyed up a bit of loose fabric and showed her the piece of carefully folded fabric. She took the fabric and pointed out to me that I had just undone the double-bow that held the rear-part of the aircract to the front part. She explained that any aircraft has a number of strings and knots holding various parts of the aircract together.
She then proceeded to write me a ticket that would put 8 penalty points on my frequent-flyer card and ban me from accumulating points and the use of any cafe at any airport for a year. To compound my misery an irate air-traffic controller then appeared and berated my lack of responsibility allowing my possessions to fly around the airport in a totally uncontrolled manner and wrote me another ticket for allowing my possessions to use the airfield and take off without permission. I suffered another 8 penalty points and a ban from all sandwich bars in all airports for another year.
Since that point I have seen many loose pieces of fabric on planes, but I now know they serve an important purpose and leave them well alone.