I would like to mention lag issues once again. The above illustration is one of the typical applications of redstone/minecarts/mobs that cause excessive and unnecessary lag (although it looks damn funny).
This is not supposed to be a rant, but more a reminder: Please be thoughtful of what you do with mobs, animals, redstone, minecarts etc. All those items are causing lag the more they are used. We have good times on the server with little lag, but we also have some times where the lag is very very heavy. As you might know, lag is measured in ticks per second (tps), and ideally we have 20tps. Many times however, we have less than 10. This will result in lag for all users. Often this is caused by automation mechanics that try to make the miner’s life easier.
If you are using any kind of redstone mechanics, I would like to encourage you to check the impact of those. This is best done when there are not too many people on the server. Check the “/lag” command before you switch on whatever you are doing, and then again while it is running. You can then judge the impact of your machines on the server. If it uses 10tps or more, you better take it down. If it is 5 tps or more, you better not run it when there are more than 10 people on the server.