How big of a bonfire can you make with a $2.6 billion cash pile? We may be about to find out. AllThingsD points us to a research note from Bernstein Research analyst Pierre Ferragu, who says that BlackBerry is on pace to torch $2 billion in cash over the next six quarters, largely because “the company is losing users at a very high pace, has a stretched working capital and massive off-balance-sheet commitments that will turn into cash burn in the next four quarters.”

Ferragu also thinks that this could complicate Fairfax Financial’s plan to buy off the company at $9 per share since many potential investors will get spooked by the company’s deteriorating cash position. In its second-quarter earnings released last week, BlackBerry revealed that it burned through $500 million in cash in just one quarter so a continued burn over the next six quarters seems plausible.