To bad Nissan Canada don't offer the March Cargo kit here in Canada. I've never had a use for back seats and the Micra does not fold flat, I've seen MetroMPG's awesome post where he built a new floor for the Micra which is nice but I don't really want any plywood or MDF inside the car.
Here's an easy way to get a fold-flat cargo area in your Micra.
The crates I used (3 fit perfectly):
20oz stackable 24-bottle crate
http://www.casemaker.ca/our-products.php