Mmkay, so this is my first project EVAR, but I'm very pleased with how it turned out. I decided to make a duct-tape corset on my friend, using a regular tank-top as the base. Unfortunately I got so wrapped up in making it (pun not intended) that I forgot to take lots of pictures of the progress. We also had to remove the corset before we could finish it up... but it was boobtastic, lemme tell ya. I have three pictures for you:
What we started out with - a few layers of tape to serve as a strengthener/soft busk:

The inside of the corset:

The form of the corset:

I haven't bought any lacing rings yet (as the duct tape will rip if I try grommets) but I'll post a picture of it all laced up and on my friend's body when I get a chance.
So it fit perfectly on my friend's body before I cut her out of it (straight up the back, with scissors), so in order to smoosh her sides in a tiny bit, I cut about a centimeter off of each side of the initial slit I made. So then it'll lace tight tight.
Another friend wants me to make one for her, so next time I'll document it better with photographs for those who would be interested. Now I know how to smoosh the boobs up better

. In all it took less than half a roll of duct tape and under an hour of time to make.
Whaddayathink?
~Schnoogles.
TUTORIAL:1. The first thing you want to do is find a willing
victim participant. They'll have to wear a tight-fitting tank top that they're willing to part with (because they'll never see it again).
2. Start at the back and stick on strips of tape horizontally starting at the shoulderblades and work down. Don't let your model hunch down - it'll wrinkle later. Keep the shirt as taught as possible to keep wrinkles to a minimum.

3. Once you've done a bit of that, you can start on the front. Start with a strip of tape around the ribcage right under the boobs (or pecs, if it's a guy...) and work up. What I do is wrap my arms around the model from behind and stick the tape on over the boobs and then pull the ends toward me before sticking them down. That allows me to use my body strength to smoosh the boobs.

4. Work your way up and down from the first strip of tape you put down on the front until your corset is the shape and length you want it to be.
5. Now you're going to cut it right off the model with scissors, so make sure they have a shirt ready to pull on. You can draw on a line straight up and down the middle of their back, if you like, or do it by eye... I think a zigzag space in the back would be cool. I'll have to try that next time. Take your scissors and start at the bottom, cutting carefully up the back. You can slide your hand under to stop yourself poking the model. Then at the top, it just comes off. LOOK AWAY, FOR YOUR MODEL IS NOW TOPLESS. Unless you're all ok with that sort of thing. *cough* Er.
6. After it's off, cut off the remaining bit of tank top you can see at the top... the straps, all of it. Then you're going to finish off the top and bottom with strips of duct tape. Just make it nice and neat.

7. Then you're going to make a space in the back to allow for lacing. It can be as wide or narrow as you want, depending on how tight it was before you cut it off and how tight you want to lace it. (bear in mind, it's duct tape, so it may rip. Be gentle.) Start with a little bit - a centimetre on either side of the slit you made up the back. You can always cut more off, but it would be a helluva lot harder to tape it back on again.

8. Finish up the space in the back the same way you did the sides and mark all along where you want the holes for lacing to be. I used a regular single-hole-puncher, but if you've got a grommetting kit, go nuts.

9. Now I am by no means a corset expert, so I laced this one with some leather cord stuff I got at a craft store. It looked neat and tidy, and was really all I had.
(DURR... being the dunce I am, I forgot pics. Again. *facepalm* sorry.)
10. Lace it up and take pictures!
(NEW PICS COMING SOON)