Minecart Revolution (MR) is a minecart plugin for Bukkit, adding novel features to your minecarts like stations, chest transfers, and lots more. You can learn the basics really fast, yet quite deeply customize your minecarts using advanced features like expressions if you so desire.
You can get the plugin from BukkitDev. If you have found some bugs, please create a ticket on the BukkitDev site. Note that this plugin is really modular; for some features, you have to download other plugins like MinecartRevolutionTags.
This article should show you how to install, configure and use MinecartRevolution. If you are looking for a german wiki go to Terraformer-Wiki. The entries there are written by the author of this article.
You can find the source code and contribute to the source repository on GitHub.
The installation process of MR is a little bit more complicated. First of all, you have to download the JAR file from one of the locations mentioned above. The next step is to place the JAR file in your Bukkit plugins folder. If you have rented some Minecraft server and you can't access the filesystem directly, use FTP or SSH-Copy/SCP to upload the file.
Now you can start or reload the server to create the folders and files that belong to MinecartRevolution. If you start it the first time MR will download another plugin called QuarterBukkit. This is necessary for MR to run. After the download process is finished restart the server. That's it.