Portable Nether is a Minecraft mod that adds a way to get to the Nether without portals. You can craft a Portable Portal which will bring you to the Nether if rightclicked, and a Nether Arrow with wich you can teleport entities and other players to the nether.

If you want to change anything about the mod or add a new feature you can message me or make a pull request.

The teleporting magic is in util/Teleporter.java. The rest is just basic setting up items and other basic stuff.