ChickenChunks

ChickenChunks is a mod that is a part of ChickenBones mods  It introduces one new type of block, the Chunk Loader. This block allows you to keep chunks loaded in memory constantly, much like Railcrafts World Anchor. In addition, it is much more configurable than its contemporaries, as it has a GUI to configure the chunk loading. It also chunk loads for free, unlike the World Anchor which requires ender pearls.

Once open, the GUI can be used to configure the loading radius and the shape of chunks to be loaded. You can also visually see the chunks being loaded by pressing the 'Show Lasers' button. In addition, the Chunk Loader is owned locally by the crafting player, so the block cannot be configured by anyone except the owner of the block.