Notch planned for crying obsidian to set spawn points, but that was later replaced by the bed. Beds are very helpful in the overworld, but not in the other dimensions where they explode. Then it came to me. I finally thought of a way to have crying obsidian with its original intent without negating the purpose of beds.
Crying obsidian is crafted with four lapis lazuli and obsidian in the middle. To activate crying obsidian in the you have to place 2 of these blocks under your bed. If you die in the dimensions you put it in, you'll spawn in the nearest bed with crying obsidian below and you can actually get in these beds, but you can't sleep. While you can have multiple amounts of these in any dimension, if you're more than 1000 blocks away, you'll spawn in you bed in the overworld or the regular point; bearing a message that says "Your crying obsidian bed is too far away". The possibilities and the benefits are endless, being able to be used in singleplayer and multiplayer.