Step 1: Gather materials etc
A: I don't know and really don't care. But is a nicer end to old stuff than the trash can.
Q: Are these useful or only for show purposes?
A: Depends on the material you used. I resharp my jigsaw blades, so I could cut 4" pine board with my pocket saw. YMMV, but they are good tools, save space and your more expensive gadgets.
Any other questions? No? Good, lets go. You'll need:
1) ballpoint pen tubes (if using bic style pens, you can still have a live pen inside -- tell you more later)
2) old jigsaw blades, small drill bits, hardened steel rods/nails/screws, old pencil sharpeners blades.
Ok, have to talk a little here: I don't use new jigsaw blades, cause I resharp mine (triangle file) and keep the new ones for my power jigsaw. You must choose the "steel part" of the tool depending on what you have available and on what you intend to do with the tool (ex.: my small saw can be a helper if you camp out; a small drill bit for PCB drilling; pencil sharpener blade good for general purpose knife and so on)
3) pliers (essential; we'll be working hot stuff here)
4) fire source (I used a lighter and a candle)
5) power grinder, rasp, files, sandpaper (optional, but gives a better looking if you grind/sand off excess)
6) good sense (don't hurt/burn youself, don't poke/cut/saw anyone, these are serious things, not knex rifles!!!)
For the pictured project, I used a hard steel nail to build an awl.