X-Wing Miniatures has been out long enough for players to accessorize their game to enhance their playing experience. Since X-Wing can be played on any flat surface without grids or hexes, creating an interesting play surface is something most anyone can do for...as much money and time they wish to spend.
First up is a simple roll of black felt. Craft or fabric stores carry these at various thicknesses and quality. Make sure to get one that isn't too springy, or the ships may tend to lean or fall over when moved. Leave it black, or flick white or yellow paint on it to simulate a star field. Felt quickly dresses up the average dining or card table.
Next is a printed surface. Several companies carry pdfs of star fields, nebulae and even space station textures that look oddly familiar. Printing them on home printers is possible, but the small paper size means pasting them down large sheets of foam core or similar surface is needed to keep the sheets from moving around. To avoid this, most can be taken to a copy center for printing on a large roll stock, providing a continuous surface.
Moving up in price are preprinted felt or vinyl mats.
After that are home built models, similar to the Death Star demo table used by Fantasy Flight.
For more, see the Fantasy Flight Games Forums for pictures and other ideas.
And for an impressive array of miscellaneous products and product reviews for space miniatures game, see the Starship Combat News website.
Aside from the black felt, I haven't used the other products or sites, so I don't have any personal experience with these companies.