So most everyone has a pair laying around somewhere. They were the headphones you purchased before you really got into it all. The one pair of headphones that you liked and spent a lot of time with. They are very low cost and they don't even rate enough to fit into your equipment list or signature here at Head-Fi.
You figure that they are maybe something that Head-Fi folks will laugh at. They don't sound as good as they used to as now you have better gear to compare them to. You still will never get rid of them for sentimental value. They can also be kind of a guilty pleasure where you pull them out once in a while and listen thinking " Ya, these were not that good, but they have a quality about them that I still like."
Come out of the closet now and post a photograph or just the name of these secret headphones. You will feel better in the end.
I have a pair of 11 year old Panasonic RP-HT850s that will never break. I keep them around just for sentimental reasons as I spent a ton of time with them. You will never see them in my equipment list or my signature as I really never use them anymore. What pair do you have?