Mount Whitney is one of those amazing and almost surreal experiences. It is not something easily undertaken, but is one of the most fun almost free things you can do in the fitness arena. The cost is minimal. You spend a few bucks on gas for the trip, food, and water. Other than that there is negligible expenditures because the equipment you need you can reuse. This includes water containers, water filtration devices, crampons, ice picks, layers of clothes, and gloves.
Mount Whitney is a 22 mile trek near Lone Pine. The first part of the way is your typical hiking trail. Enjoy the hiking part and take in the scenery, which is amazing. After the hiking portion you are faced with some serious climbing. Once you reach the cables the hiking feeling is gone. You almost feel like you are doing real mountain climbing. I use the world almost as not to offend those who are mountain climbers; I am not although I am certain that Mount Whitney is easy compared to summits others have reached.
There are several ways to proceed with the hike. The first is to play it as a 3-4 day journey. I recommend this option if you are highly experienced or acclimated to high altitude. If you are more experienced and willing to go hiking and climbing with a head light you can do this in about 2 hours or less.
On the way down make sure you take the right trail to avoid ending up at the lake and perhaps having a horrifically long day or cold night. Since it is long consider spending a day at high camp on your way down so you can enjoy the scenery a bit more. Also make sure to bring food; consider having about 200 calories each hour.