As of late 2009 DVD Zap cancelled its rental option and displayed a sales liquidation page instead--even though they're out of the rental business, we've kept this review as it was for posterity.
To our knowledge this is Canada's only French-only website, an excellent choice for a wide range of films in French. The site appears well-designed, listing 22 genres, though total film inventory is not listed and appear to be on the small side compared to the larger companies, as you'd expect given the smaller number of French vice English DVDs. They even have an option to list film details in French or English.
To their credit, DVDZap has a customer service phone number, as well as an online help box to note problems. Given our limited knowledge of French, this is as far as we can review the company; customer comments going into more detail are welcome.
Prices: DVDZap offers a two-week free trial as well as three discs out unlimited rental for a very competitive $19.95.