Not only is this a super-classic multi-day one-way trans-sierra backpacking trip, it is an ideal backpacking trip to do from a plane. There is a taxi/shuttle available from the Mammoth airport up to town for the night, and then up to the trailhead the next day (actually, where you take the bus into Devil’s Postpile to the Trailhead), and then there is a long shuttle that once each day travels from Yosemite Valley back to the trailhead at Mammoth Mountain ski area. Now, having said that it didn’t work out that well for me. Mammoth airport was closed in the summer of 2008 to enlarge the runway, so I flew into Bishop.
Actually, even if you don’t have a plane and you drive, that shuttle back through the sierras is invaluable in allowing a one-way trip across the mountains. You need a permit and some planning to do this trip, but there is a lot of information on the Web and in books on the John Muir trail. If you do fly and stay in Mammoth Lakes the night before you depart, you might want to stay at the beginning of town (e.g. the Shilo Inn) so you are within walking distance of the visitor’s center where you have to pick up your permits. Then the shuttle can take you from there up to the ski area for the bus to the trailhead.
The trip was wonderful – a true classic. The highlight was climbing Half Dome by moonlight, then watching the sun come up from the top. We did the trip in 7 days, but also stopped in Tuolumne Meadows for milk shakes, some trailfood and a fresh breakfast the next morning before heading out again.