back at CES, about GM's aftermarket mirror that would make the OnStar service available to most cars, including those from its most hated rival in Dearborn. No? Don't worry, here's the skinny: the OnStar FMV will let you have the company's popular blue button technology in over 90 million automobiles. Meaning that almost anyone can now reap the benefits of features like automatic crash response, turn-by-turn navigation and hands-free calling. You know... unless you're cruising in the General Lee, or something. Selling for $299.99, plus a $75 installation charge and $18.95 per month ($199 yearly) subscription, the high tech rear-view mirror will be on shelves at Best Buy starting July 24th and is now available for pre-order. Before you throw down the Benjamins for this automotive security blanket, you might want to double check that your car is compatible -- check the full PR to find out how.