My MiL's moste favorite sweater hooked a paperclip, which nestly snapped one strand. It's double knit, which is fun, and also black, which severely limited the times of day I could work on it. Only a few stitches on the inside needed addressed, so I almost just tacked them down inside, but once I got going I figured I'd do it properly and get 'em all in one continuous graft.
The "needles" are bits of wire I filed the ends into rounded bits--I don't remember what gauge it is; 16?
Every day I get closer to sourcing those specialty 00000 knitting needles I know exist...