Like the fantasy Master Maze series, the Sci-Fi line from Dwarven Forge is modular, comes pre-painted, is designed for use with 25mm minatures and has a 1" grid pattern built into all the floor designs.
From the Publishers website:
The Sci-Fi Alpha Expansion Set allows gamers to greatly customize their Sci-Fi gaming environments by providing many new exciting pieces.
The set includes:
(1) 6 x 6 floor tile with removal insert
(1) 4 x 6 floor tile with removal insert
(4) Power Coupling Pillar
(1) set of Ramps
(1) Hatch OPEN floor piece
(1) Hatch CLOSED floor piece
Note that the floor tile, pillars and ramps can be combined to make multiple levels in a room, thus adding to the tactical versatility of the set.