Overview
A great alternative to the usual Army Pass, Winter Pass (the unofficial name, as I understand it) offers a moderate snow/ice climb without the need for significant protection. It is steep, however, and of course ice ax and crampons are a must during the obvious climbing season. While not limited to winter time, this route requires decent conditions to climb.
Also, this route offers a much more direct approach to Langley's summit, as it's further north than Army Pass, putting the climber just below and south of the summit block.
This climb could be done in a long day, but I'd recommend getting to the Cottonwood Lakes basin the first day, then hitting the summit/descending on the second day.
Getting There
As with the Army Pass route, take Whitney Portal Road out of Lone Pine, then a left onto Horseshoe Meadow Road up to the Horseshoe Meadow trailhead.
Take the trail to Cottonwood Lakes, but instead of heading west to Army Pass, stay on the main trail all the way into the basin. Make your way to the northermost lake (#5, it's big), and Winter Pass is on the northwest corner (farthest away from the beginning of the basin).
Route Description
Winter Pass is along the northwestern most corner of Cottonwood Lake #5. Make your way around the lake to the boulder field just below the pass. Depending on conditions, this field requires some class 3/4 scrambling to negotiate; once you're through the rocks, pick the best line up the pass.
There may be a lip or cornice near the top of the pass; again, it depends on conditions. Use caution at the top as it may be close to vertical for the last 10-20 feet.
Make the saddle and head right (north) to the summit. Rinse and repeat.
Essential Gear
Of course you'll be wearing your crampons, and have your ice ax, because you're not stupid.
I wouldn't laugh at anyone roped up, but protection isn't totally necessary. Deadmen/pickets would be the anchors of choice, should you choose to bring snow protection.
External Links
Info on current conditions, TH/roads, etc.