At SEMA, different car gadget technologies were crashing into each other all over the place. Initial had a portable navigation unit and DVD player, the GD-58, at its booth. The combination makes sense, as both require an LCD screen big enough for maps or movies. Initial's expertise lies in portable DVD players, but it produced the GD-70 navigation unit earlier this year. The GD-58 combines the two in a nice-looking package. The navigation relies on SD cards for its maps, and I found that inputting destinations is fairly easy with the large, 7-inch screen. The unit opens up like a clamshell, revealing a DVD drive, making it a good companion on airplanes. And the navigation makes it perfect for the subsequent rental car.