Within minecarts, I am sure you have all heard of boosters- this takes it up a bit, by colliding 3 of them, and forcing 2 to push each other at the same time, resulting in a powered mine cart, that goes forever.

Here's how it works-

First, build this, with just tracks. Elevations are horizontal, all the way.

Elevation|
        3|  /---\
        2|  ||  |
        1|  ||  |
        0|  ||  |
        0|  00  \________TO REST OF TRACK

Then, place a cart here and here-

Elevation|
        3|  /X--\
        2|  ||  |
        1|  ||  |
        0|  |X  |
        0|  00  \________TO REST OF TRACK

And finally, here

Elevation|
        3|  /X--\
        2|  ||  |
        1|  ||  |
        0|  XX  |
        0|  00  \________TO REST OF TRACK

Riding in them usually fails, so place a couple of carts after it to make a nice train that won't fail. Glitch will show you, as I showed him and a few others. When building tracks, they may shoot out randomly at hard turns, so plan ahead and don't place too many of them. Anyways, don't hate on me if you've seen it, you all know I'm new/not playing SMP regularly... just freebuild. Also, based off the egotistic names given by Fumino, if it is new, it shall be the "Fumi-Booster".

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Inferiority is the true ascendancy.

Cool idea, but I only name stuff after me that I created, not others (same way most things in the world is named). So call it the Fehzor-booster.

Don't know if you know this one or not, but to get full speed that never stops, just place 4 tracks in circle next to your track. Place 2 carts in it, which will collide and take off spinning constantly. Then when you ride past it, it will launch you, and never stop.

Edited:

Did a ton of tests today and got the perfect, easy to make launcher, that resets itself.

Legend:
  T = Minecraft track
  R = Redstone
  B = Block
  BT = Button
  RT = Restone Torch
  ( ) = Whatever is in here is in the same block space

  R R R R R R (RT B) R R BT
  R     R
T T T T T T
T T     T T T   <-- beginning of your track
            T
            T
            T
            T
            etc...

In the track circle to the left, place 3 carts in it. Now just throw you a cart at the beginning, hit the button, and your off, never losing momentum. The redstone can be wired up differently, this is just a basic easy way of showing it.

Note: It HAS to be exactly like that, if you make the launcher longways, it will still launch you, but it will lose momentum.

Also, sometimes the carts disappear from the circle, don't worry though, the carts are still there, they are just invisible. When I made the field test by my house, I came back to it over an hour later and it still worked perfect.

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I used to do drugs. I still do, but I used to, too.
-Mitch Hedberg
Front page of a very old website of mine back in 1999:
Hello, today is December 30, 110 and this site is Y2K compatible.

Y'know you can use F1 and F2 to take pictures, crop/shrink them (if necessary), and attach them here, right?

It saves to a random crazy folder, but if you check the texture pack folder under the appropriate menu, and go up a folder, you'll see the screenshot folder.

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I'll stick with the classic "Print Screen" key. Yeah putting some screenshots up would make it a lot easier to understand, next time I'm in game I'll take some screen shots.

I had to leave in a hurry today, so I accidently left a temp warp up to the one I installed on the railway system. You can see an example of it with /warp fumitemp. Feel free to remove that warp at anytime, next time I'm in game, I'll remove it if it's still there.

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I used to do drugs. I still do, but I used to, too.
-Mitch Hedberg
Front page of a very old website of mine back in 1999:
Hello, today is December 30, 110 and this site is Y2K compatible.

I made a station-ish thing for Ollie out of this, it kind of uses the same thing as yours, and works fairly well- it shoots all the carts out and thus pushes them all to the end of it- Glitch also made a fairly cool booster-ish launcher type thing like yours, his was pretty nice looking as well.

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Inferiority is the true ascendancy.

Looks like notch FINALLY fixed these for good.

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Not in cruelty. Not in wrath. The Reaper came today; an Angel visited this gray path, and took the cube away.

More like the hMod team... They made like 20 commits related to vehicles in the past few days. :-P

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War does not determine who is right - only who is left. - Bertrand Russell

Awwww, Notch fixed them? I guess it is for the betterment of MineCraft. I want to read about it, but the "Word of Notch" blog thing is down for me, so I can't.

EDIT: Got on it, and read stuff. Lots of good bug fixes. I'm rather pleased with it.

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Inferiority is the true ascendancy.

Sorry we changed it to an easier one that doesn't throw the carts at you. Fumino designed it.

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Breasts

Oh, yeah. I saw. It doesn't get you as far though- or didn't when I used it, though it might have been because I hit someone, and was slowed a bit. Either way, good job Fumino.

_________________
Inferiority is the true ascendancy.

Yeah maybe it's glitched but if cart side by side gets fixed then we will need to revert to Fehzors when the carts are sent with you.

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Breasts