I'm a huge fan of Nolan's batman trilogy and absolutely love the Joker portrayed by Heath Ledger. In this instructable I made a shoe with a knife in it, like the one Joker had in the movie (he used it when he crushed into Wayne's party)
Hope you enjoy
Step 1: Materials
1. Shoes with thick sole (converse, vans or any other shoes like these would work)
2. Knife, double action out-the-front (with sliding button at the front, not on the side)
3. Cutting instrument. I used my dremel tool, because its easy and fast, but you could probably do it with a knife or something else.
4. Glue (any very strong glue should work)
Step 2: Outlining
Place the knife on the bottom of your shoe and use the marker to outline the size and shape of your knife.
Step 3: Cutting
Cut the sole of the shoes, just a little outside the marked line, so the knife can actually fit in the hole.
Step 4: Taking Out
Take out the sole that you cut out. You can help yourself with the knife.
Step 5: Sanding
Most likely the knife won't fit in nicely just yet, so use dremel tool (sand paper can probably work too) to sand the edges and the bottom to get a nicer fit.
Step 6: Gluing
Glue down your knife. It probably won't glue down right away, so you can tape it and place your shoe under the heavy object over night.
Step 7: Done
Open your knife by sliding your foot backwards, and close it by sliding your foot forward.