Redstone paste is like redstone dust - in a way. The difference is that it can be placed on walls and ceilings. It cannot connect to normal redstone dust, but can still receive power from redstone torches. The crafting recipes, shown above, craft 2 pieces of redstone paste. The current carries as far as normal redstone dust.
Recipe (Pretend that the magma cream is redstone paste)
Using gold as a conductor, carries current 2x as far as normal redstone. It can also be placed anywhere in the air. Crafting recipe crafts 2 (or 3?) redstone wire pieces. Redstone wire can be powered by buttons, levers, and power sources (see below), but not redstone torches. Redstone wire connects to all blocks.
Redstone Power source
Recipe (again, the cream is supposed to be redstone paste):
Provides power to adjacent blocks, and can be placed anywhere. Unlike redstone torches, this cannot be un-powered, making redstone torches still useful.
...That's really it. If this was implemented, I think a lot of redstone techies like sethbling and FVDisco would make really good use out of this. Keep in mind this idea was off the top of my head so it's not as well explained as my other suggestions, but I wanted to get it out there and see what people thought of the general idea before putting a lot of effort into it.