When I was writing my master's thesis, it was the last thing I wanted to do and I kept thinking of MORE FUN things. I found it helpful to write down those fun things on a piece of paper as a "promise to myself" to look at later; this helped me get back to work because at least I did something with the idea.
The Pickle Jar is an actual glass jar that once held pickles. Next to it is a square pad of paper, about 4 inches on the side. To get unrelated thoughts out of my mind, I write down a brief synopsis down, fold it twice, and put it into the Jar.
-- from Hold That Thought! via davidseah.com
The interesting thing about pickled ideas is they tend to expire. After writing my thesis I opened up the jar and read through the ideas and none of them were interesting anymore. These days, I no longer pickle ideas as a way to manage distraction, and I am not afraid of forgetting them because I no longer have that fear of losing information I used to because I can generate ideas at will.