What kind of bike do you have?
Are you going to build it from he ground up?
Does it have to be a traditional type of bicycle or can it be something like a trike?

If you want to go fast, i would suggest to first look at what you have or want to ride.

So... how fast where you thinking to go?

http://www.youtube.com/watch?v=HchmcZvgoBY&list=UUrTQ6ERhmiS_tgk0rRKKIDA&index=3&feature=plcp

Check out this video.

Bigger front sprocket and small back sprocket.

I have A sport bike... i have disc brakes for both wheels.. a double stand... changed grip for style... removed v - brakes... change to slimmer tyres... remove all stickers... white colour to feel fast.... and also use MAXXIS TYRES for a good grip.. thats all!!!!!

first of all you want a light bike, but this is expensive to do. what you can do is save weight wherever possible. maybe take off the front or rear break (i would take off the rear because front has most of the breaking power)...etc. second, you may want to get a 29'er. although 29 inch wheels require special frame and fork, you gain more overall top speed, but you lose torque. if your looking for more acceleration i would run 26 inch wheel on the front, and 24 inch wheel on the back. also a bigger front sprocket, and smaller rear sprocket helps to give you more top end speed. remember to utilize all your gears though, this will save you a lot of energy. as for lubrication, i would recommend tri-flow. ive used it for about a month now, and it has helped a lot. only use this on the hubs and chain though. a rigid front fork will also help you gain more speed because it does not absorb the energy you put into pedaling. dont wear big coats, wear a slim fitting T shirt and some shorts. also raise your seat up so that you can just barely lock your knee when the pedal is at the lowest position. this will give you better muscle efficiency and will force you to lower your body which gives you better aerodynamics. and if you want, a good plate of pasta or a potato along with about 500 mL of water before you ride will help too. they are full of complex carbohydrates and will give you more energy.

smaller cassette.

Get your bike set up properly. There is a very small "sweet spot" where you get far mor epower for the same amount of effort. I was never able to afford a high-end setup job, but I've borrowed bikes from a friend that, although not quite right for him, made everything 4x easier for me than my regular "looks about okay" setup.

Get Cleats, they increase your power by about 30% because you can pull up as well as push down. they also keep your feet in the correct position. MTB cleats are best for casual riding becasue they are cheaper than road cleats and you can still walk normally with them on, shimano cleats are fairly good, thats what i have and i am very happy with them

larger crank

If you're running knobby tires and you do most if not all you’re riding on roads/bike paths then switch over to slicks. Slicks are much faster. Toe clips/straps also make a huge difference, which is why racers ALL use them, they let you pull on the up stoke when sitting and they keep your feet locked in when you want to get up to lean forward and run on your bike. When I was younger and in much better shape I would run on my bike letting the clips hold my feet on the peddles, I would lean so far forward that my toes would be pointing down at the road yet I never had to worry about slipping off, you just cant apply that kind of power to regular clip less peddles your feet will just slide right off and send you teeth first into your bar. They take some getting used to but once you do you'll never want to ride without them Bar extensions are also good for giving you a better hand position when you want to stand and pump the bike back and forth with your arms in a counter stroke to your legs for more power, though you generally only do that when you’re sprinting. Still it's nice to be able to change hand position even during casual riding. Oh and the person that said remove one of your brakes NO NO NO!!! Never remove your brakes, if you can’t stop effectively then more speed will only get you killed. If you’re really that hard up for a few extra ounces then toss out your seat and ride standing lol just don't toss out your brakes! They help keep you alive.

absolutely; check out what I did-
http://nkevin90.livejournal.com/23481.html#cutid1

From simple to complex, and mostly cheap to expensive:

• put your seat up as ledzeppie suggests
• oil everything except your brakes and tyres :) especially your chain, and make sure your wheel bearings are clean and greased
• adjust your brakes so they don't rub on the wheels when not in use
• inflate your tyres more
• invest in pedal clips
• get narrower slick tyres, knobblies are terrible for rolling resistance
• invest in drop bars or narrower standard bars
• get your wheels trued to reduce wobble, and make sure your tyres are evenly set in the wheel rim all the way around
• buy a racing bike with a low weight narrow frame, narrow slick tyres, drop bars, well adjusted brakes and pedal clips :)
  

Riding tips:

• keep your head down
• hold on to the middle of your bars near the headset clamp rather than at the ends
• wear more aerodynamic clothes
• anticipate traffic as you would if you were driving a car, it saves energy and means less braking
• tuck in, especially when freewheeling downhill, to reduce resistance
• take the straightest path you can, use a "racing line" on corners when it is safe
• learn to use all your gears- ideally maintain a cadence (pedalling rate) of 60-80 rpm. I think "tick" to myself every time my right foot reaches bottom dead centre and change gear to get that at or slightly above once a second

Have you tried a motor?

pedal faster?

Kites? Sails?

. Reduce weight. It it doesn't hold the bike together, get rid of it. . Reduce drag. Spoke covers, &c. . Reduce friction. Make sure tires are properly inflated. Make sure everything is well lubricated and use the least viscous lubricant you can. . Use a different gear ratio.