A few years back, I was heavily into the anime FullMetal Alchemist, and had purchased the metal plated messenger bag:
I have since fallen out of the FMA fandom, but I still used the bag a lot, as it is the perfect size for carting around my 13.3" Vaio.
I thought several times about doing something to the logo, and finally tackled it this week.
first of all, I made a slit on the back of the front flap. to my surprise, the metal plated "fullmetal" was just hinge clipped (know what I mean?) onto the bag with ties on either side of it, so after I pried up the ties it popped right off the front.
The "Alchemist" part prooved to be a bit harder. I first tried a seam ripper on the red threads and between working it on the front and on the back I got as far as getting of the "T" in about a half an hour. Deciding that that was going to take too long, I looked at it again, trying to figure out if I could somehow cover the words. That looked too bulky, but I happened to have an old messenger bag/purse lying around that I could cut apart. Through the inside flap, I cut out the word "alchemist" from the front piece, and then sandwiched a piece of fabric between the front and back to cover the hole, and THEN I sewed on my new decals, to make this:
*edited to add* here's a link to the VERY LARGE photo of the close-up if anyone wants to see it larger than life: http://www.beccajanestclair.com/lj/P9301011big.JPG
if you look very closely to the right of the horizontal line in the UK flag, you can see a little bit where the piece was cut out and replaced, but other than that, it looks beautiful!
I also tried turning part of the old messenger bag into an accessory bag for my laptop peripherals, but i'm still tweaking it.