Since I work from home and also like meditation, my take a different approach than other answers.
I only have one rule about what NOT to do: Sitting in front of my computer
Working from home means lots of time in front of my monitor and little movement, so I focus my breaks in anything that makes me move. Since I also do sitting meditation every morning and every night, I do not want those 5 minutes to go by just by being blank.
Normally I choose a physical task that can be done quickly. It can be some cleaning, doing the dishes, preparing the food I will cook later, brushing my teeth... however whatever the task at hand is, I strongly insist in clearing and focusing on the sensations of the task at hand, call it, awareness meditation. For example, while doing the dishes I do not use music, just focus on the present moment, feel the temperature of the water in my hands, the sensation of the foam...
Although it looks boring, I also found great learning QiGong. It is not the type of meditation I like doing during a long time, but it is great if you do it for those short moments because you can start/stop immediately, you move constantly and give a gentle stretch to your body.
QiGong might be one of the best 5 minutes breaks I have. Also one of the most luxury allowance for a home worker, since I could never imagine being in an office full of people, standing up every 25 minutes and do the movement dance with serious/focused while I walk across the desks of my coworkers ;-)