When you buy a pair of Poi your kit will also include: 4 AAA rechargeable batteries, two D rings, a plastic key (to aid opening and closing the battery contacts) and a manual.
It is possible to change the stored patterns/sequences but your computer must be able to run a special program on Windows or a Mac. It is fairly complicated to write your own sequences. A manual and a test program can be emailed to you if you are interested.
The Poi cost £180 per pair including postage.
The programming kit costs an additional £20.
Additional pairs of socks: £20 per pair.