Back in May, bhtooefr posted on Cemetech about a boondoggle with the HP Prime: Revision A devices could not use the promised wireless module. User balrog popped into IRC this morning and dropped a bit of news on us; Europe now has a new revision of the Prime in Europe. This promised Revision C fixes problems that they were having with the wireless kits that they have, and it seems the wireless kit itself is now available for purchase.
Announced in June 2014 in a Google Groups post, this new revision remains difficult-to-find in the US. The wireless device itself is described on educalc.net. Available information stresses that the wireless device, which strongly resembles the bright yellow wireless module for the TI-Nspire, can only be used for base station-to-calculator communication. Calculator-to-calculator communicate remains possible only with a wired cable.