1) Make sure your fingers stay close to the keys, even when you are not using a finger to press a key down. This helps because your finger has a shorter distance to travel before making contact with the key to press it down. Use a mirror to check this and practice keeping your fingers close to the keys so you remember what it feels like. No matter how fast your fingers get, you'll always be just a little slower than you could be if your fingers are always flying way up off the key when you aren't using it.
2) Practice doing short bursts of notes quickly - trills, segments of scales, even stuff from music you are working on. Start slowly and gradually get faster. Once you think you have it pretty fast, challenge yourself a little bit and see if you can do it even faster. Once you have it faster, challenge yourself again and see how fast you can go.
3) Practice fast passages by slowing down the notes, but continuing to move your fingers quickly. I know that sounds kind of contradictory, but what I mean is that when you change the fingering to play the next note, use a sudden motion instead of a slow one. When we play slower passages we also tend to slow down our finger motions between note changes. Resist this tendency. This doesn't mean you should be slamming your fingers on the keys either. Continue to use a light touch, but just move your fingers fast. It's like running the 1 meter dash. You can practice slow passages this same way.
Of course, you can use these techniques in conjunction with pretty much any scale, arpeggio, method book, etude book, basically anything. The important thing is to keep pushing yourself - and make sure your fingers stay close to the keys.