DIY Sreampunk Inspiration: Steampunk Portal Boots by batman-n-bananas at DeviantArt here. Also check out her Steampunk Satchel, Wallets, and Aperture Steampunk Handheld Portal Device - AMAZING. First seen at EPBOT here. How she did it:
“These started as two pairs of shoes, one cheap pair of black pleather boots and an old pair of canvas shoes. The heel ‘spring’ is actually plastic tubing as I could screw this straight into the heel to secure it firmly (plus a lot more sensible to walk in).”
I have a bit of a steampunk fixation, and these just blew me away.