I'm pretty sure that Pokemaster's link is pretty much the same thing, but...
There's no room for setup with Pikachu. With the frail defenses, Pikachu will never take more than two hits in the standard game, and will be lucky to take more than one. That means no Agility and no Nasty Plot.
This is the standard set for NU/UU Pikachu. It's a set I usually see when I see Pikachu being used, so I may as well credit this set:
Thunderbolt (STAB)
Grass Knot (Great Ground-type coverage!)
Signal Beam (A nice coverage move)
Hidden Power [Fire] (Great wall coverage, as Ferrothorn, Bronzong, and other Steel-types won't be taking kindly to it)