I have used a talisman, but more as a reminder to do an RC than as an RC in itself. I sometimes carry a ping-pong ball in my pocket, and when I become aware of the ping-pong ball, I do an RC. When I first started carrying it, I used checking whether the ball was there as an RC, but after I had a dream in which I didn't have the ball in my pocket, I stopped doing that. But by that point it was still an item I associated with dreaming, so I still sometimes carry it around with me as a reminder to do my day work.