Bleacher Running:

Extremely simple; run up and down bleachers/stairs. It's basically a resistance training program for your legs. The fight against gravity as you power up a steep incline translates in both speed and confidence size.
There are two different types of bleacher runs. The first would be to find a set of bleachers, power up the stairs, then take your time coming back down. This is similar to interval training. Really fast up, recovery pace down.
Another form of a bleacher workout is to run "repeats". Find a set of bleachers, and just take the time to jog easily up and down them for 5-10 minutes so that you are adequately warmed up. Once you have jogged at your warm-up speed, try and build your speed/power and run at a hard but sustainable pace to the top of the hill, turn and jog or walk back down. Repeat this 3-5 times or a many as you can, then cool down with a 10 minute jog.