You convert your powerpoint presentation using software sent with the unit then simply link your Blackberry to the Impatica device (our IT manager is going to look at the BES version of the program depending on cost). Very cool stuff. The only downside is you still need a power source for it but they use a USB interface with plug (the same one that charges the Blackberry will do).
*I bought this commercially and have no relationship with the company. I just like the product.