Come to Paris
Offers online reservation of tables at 2 and 3 star Michelin restaurants.
http://www.cometoparis.com/restaurants.html

Grandes Tables
Book tables at top restaurants at the last minute and save money in the process.
http://www.grandes-tables.com/

Most Charming Bistros of Paris
Reserve a seat in one of 500 restaurants online.
http://www.mostcharmingbistrosofparis.com/

Surf and Book.com
Book a table online using this website.
http://www.surfandbook.fr/
http://www.surfandbook.com/