You can now design your own personalized Keepall, Pegase or Speedy with the new Mon Mongram feature at Louis Vuitton online.

There are several different colors of stripes and you can add your initials. (The concept is very similar to what Longchamp has been doing for a while with their Le Pliage bags - Le Pliage Sur Mesure. I wrote about those a while ago.)
Here's what I came up with:
The premium for the personalization is $280! Yikes, a bit steep! (the regular Speedy 30 is $690)

The main reason companies offer personalization (such as monogramming) is to prevent returns. iPods, turtlenecks, LL Bean backpacks, whatever: it immediately renders all product returns void. Strange that the markup is so high for this service!
Good point! As if their margin wasn't high enough...now they have no returns liabillity!