By definition (and except for pinhole photography and photograms) photography involves glass (and sometimes plastic). I enjoy shooting non-optical glass as a subject for images. This image is a shlf of glassware at a thrift shop.
Another working trip to Calgary this week; I had my DSLR with me to do a portrait for a co-worker, but no real time for photography otherwise. I did notice an interesting light pattern in my hotel room though. You shoot it where you find it.