In all seriousness though, you really can't beat a nice flight of stairs to train for the hills, and - dare I say - it's actually better than the machine version. The reason is resistance. The weight you add to a StairMaster just doesn't equate adding weight to your back.
A friend of mine who is a first-rate alpinist claims that stair climbing with weight is the single best exercise you can do to prepare for an expedition. His workouts only last 20 minutes but are grueling. A version of this will get most anyone ready for adventure in the hills, regardless of your fitness level.
What you need: a good pair of sturdy shoes (or boots) and a pack. I use running shoes but many people will prefer more support. Lightweight hiking boots or beefy trail running shoes are best. Your pack should be one that contours well to your back. And you will need some stairs. If there is a university nearby, chances are the bleachers at the football stadium will be perfect.
To start: Start slow (it's beginning to sound a little rote here but I can't emphasize it enough). If you are in poor shape you should walk up and down the stairs without weight for 20 minutes. Go as slow as necessary and don't worry too much, most people will improve rapidly.
If you are fit, still start slow. If you've been doing some stair running, start with a light pack. If you haven't been doing any, start with no weight. If you start with heavy weight and hammer yourself, you run the risk of thrashing all of your Type IIB (emergency) muscle fibers and limping around for a couple of weeks. Trust me, I've done it. The reason is the descent. It's plyometric (adding more resistance than body weight) already and the weight of the pack makes it somewhat severe. Do not push until your legs are shaking during the first couple of weeks.
The weight: Work up to a weight that is similar to what you carry in the mountains. I usually put a rope and rack of climbing gear in mine. Sometimes I will also add water. If you find the bulk uncomfortable, just use weights (or rocks), but keep in mind you will have to deal with that bulky pack at some point. Add weight gradually as you get more accustomed to the exercise. Don't up the 20-minute time until you have maxed out your weight. By maxing I mean the weight you may be carrying in the mountains. You needn't ever exceed it by too much unless you are going to a very high altitude.
The workout: What you want to do is go up and down the stairs Éduh. Okay, start slowly and hit every other, or every third step (stair dependent). You want a fairly big step that works the quads in your upper legs. You don't want to bounce off your calves like you do when running.
Many factors are dependent upon the stairs you've chosen, but a good, long flight is best. At the top, without rest, turn around and come down. Go slow on your descents for the first two weeks, then speed up as much as you want. Keep in mind that down is the high-impact direction, so how quickly you descend depends upon what type of event you are training for. Many people have no reason to ever take the risk of speed descending, while others thrive on it.
After a couple of sets I really try and hammer, going as fast as I can (again, not in the beginning). After a few of these I spend the rest of the time just trying to keep moving. The perfect 20-minute set has you feeling like you could go faster at first, but finding it hard to continue by the end. Over the last 10 minutes, the crest of each flight should have your quads pumped and you should really be sucking wind. If you're hurting at the top, take a break but walk around - don't stand. Once your legs start feeling like jelly it's time to stop for the day. By continuing, you risk over-training, and once you over-train you need a long time to recover.
Frequency: Three to four times a week tops; once or twice is still effective. Four times a week for six weeks should have you ready for Everest. Have fun!