I think the dispensers in minecraft should be able to spawn minecarts on a rail, just as they do with the monster eggs! Think about how easy a cartstation could be? And if that would be possible I think a minecart that traveled directly into a dispenser should be obtained by it.

I think someone should make a mod of this :) (but then I wan't credit for making the idea!)
But for now, I stick to this awesome station, I just improve it a little bit: http://www.youtube.com/watch?NR=1&v=2YyPlBOMUn4&feature=endscreen

Also i found a bug in 1.2.5, if you make something like a pez-dispenser but let the carts fall down on eachother in the bottom, (works only with three or more) and if you have a powered rail on the bottom and make them go, they will travel in all eternety (flat land) they don't travel as fast as you are walking by yourself, but you can acually sit in them. This is pretty awesome if you want to go somewhere in survival but don't want to eat all the time :P (make sure there are no hills tought ;( And if you use many enought you can acually turn once without the carts going everywhere!

Please respond if you liked my idea, or tips to make it better :) (Pardon bad english!)

The pictures are from my creative flatland, and the structure is the one in the video above. And the textures is my own customized painterly pack (find the original here http://painterlypack.net/)