What do you do with leftover incense?

Both at home and in the temple, we use solid incense sticks. In other words, there’s no wooden core like many incense sticks have. This means that the burnable part of the incense sticks stands upright within the ash in the incense burner. Over time, many of these small leftover pieces accumulate, filling containers.

I’d like to know what you do with this leftover incense. Is it possible to reuse it?