When creating tileable textures there's a very simple trick in photoshop, using the offset tool. If one wants to make an image that serves as a 2d tileset it's not much harder, you make one tileable texture and then create the variations while preserving the borders, after that you can glue all variations in a single image file.
I'm working on a 2.5d game tile based. Meaning the world is stored in a 2d array, indicating what's ground, wall, water etc and represented by 3d models. The problem now is to come up with a workflow for creating these 3d tiles! Each tile model has to flow continuously to every other tile, both texture and polygons.
I would love to hear some thoughts on the subject and how are people solving that obstacle, and with what softwares.