Not everyone has the budget to get themselves a massage chair, be it in their home or office. An inexpensive alternative to a full-blown massage chair is a massaging insert or cushion. These simply sit onto a regular chair. Of course, being fairly thin, they are somewhat limited in terms of how much motion they can generate. Still, if you want a cheap way to relieve some tension as you sit, they may be a good option.
Massage Chair Insert:
Massage Chair Insert pictured: Wagan IN9988 Black 12V Ergo Comfort Rest Massage Magnetic Cushion.