The South Face route up Lost peak takes a line of least resistance directly to the summit from the saddle between Lost Peak and the Wedge. The wall is steep enough to keep your attention, and even if the climbing isn't technical, avoiding loose rock and hidden cactus will keep you on your toes.
The route takes a low-angled ramp system up to about half-way up the face, above which is a right-facing corner. Stick to the corner, or stray out onto the face to the right.
The route starts about 50 ft below the saddle between the Wedge and Lost peak, on the West side. Descend by rappelling the route, or rappelling off the north side of the peak into the gully that leads to the South side of Dingleberry.
Light rack consisting of a set of wires and a hand-ful of runners should be enough for experienced climbers. For those who take 5.5 climbing more seriously, some cams up to hand-sized could come in useful as well.