For those of you with multiple SD cards, but cameras that only take CF cards, you might be interested to know that they make a SD to CF adapter. Mine is by Semco and I bought it from Amazon years ago. I see variations online including one by DigiGear on both Amazon and B&H. Mine is SDHC compatible, but there are also SDXC compatible models out there.
These adapters are slightly larger than your typical CF card (which is Type I), so make sure your camera can take Type II cards which thicker to accommodate tiny hard drives (remember these?).
I assume this is to maximize the amount of space they have for the design as an SD card has to fit inside the adapter. Unfortunately, the card loads in the side so you still have to take out the adapter from the camera to get the SD card out. This might be on purpose in order to stop the camera or computer from reading/writing to the card.
Mine worked on my Canon 7D and Canon D60 (yes D60).
I tested this adapter years ago with ATTO Disk Benchmark (I mislabeled it on my card) and found it writing around 15MB/sec. Informal testing confirmed the save time on the camera to be about 15MB/sec. It doesn’t matter the speed of the SD card. This adapter is just slow (including too slow for 1080p 30fps video).
The above images were shot with a Fuji X-E2, old Nikon 50mm, 10mm extension tube and generic ring light. You can see that the extension tube exaggerated the swirly bokey from the 50mm @ f/1.8 and the right light made it very difficult to avoid the reflection from the end of the shiny adapter.
The surface is just a piece of black non-slip mat on a computer lap desk which I rolled up to prop up the cards to show off the end. I just wanted to try something different with what I had handy.