Archive for the ‘Hacks’ Category

Magnetic Fingers

In an attempt to gain a sixth sense for the electromagnetic fields around me but without resorting to Steve Haworth-like implants I decided to experiment with small (2mm x 1mm) N45 Neodymium magnets and nail polish.

Nail polish and magnets

After playing around with various numbers of magnets and formations I came to the conclusion that it was best to have a few lining the edges of my nails. That way I could feel the magnets move against skin (which would be more sensitive than the nail area) while the magnets could be firmly attached to the nails. I also found that trying to place as many magnets as possible on a nail had the problem of them pulling together and detaching due to the nail surface being curved, as well as having the undesired effect of being shiny and eye catching.

Magnetic fingers

The end result was slightly reminiscent of the website Human Upgrades. Sadly though I can’t feel the oscillations as described with the implant equivalents but I can feel the presence of magnets nearby such as near the speakers or the lid of my laptop. The sensation is similar to someone tugging at your nail (obviously) but also feels a bit like when the hairs on your arm stand on end. A future attempt will probably involve slightly larger magnets and perhaps attaching the magnets to the fingertip rather than nail.

Oyster Card Hacking

An Oyster card, as described by Wikipedia, is:

a form of electronic ticketing used on public transport services primarily within the Greater London region of England. It is promoted by Transport for London and is valid on a number of different travel systems across London including London Underground, buses, the Docklands Light Railway (DLR), London Overground, trams, some river boat services and most National Rail services within the London Fare Zones.

This describes how to extract the RFID chip from an Oyster card.


  • Oyster card
  • Acetone (commonly found in nail polish remover)


    • Submerge card in acetone until it softens.
    • Peel off layer of plastic and submerge again.
    • Repeat until chip is visible.

The wire for the antenna of the chip is very fine so it’s easier and quicker to extract the chip without it and opt to solder on your own antenna. The contacts on the chip are quite weak so care has to be taken not to break them off (They look like wings on either side of the chip. Should be easy to spot if you look at where the aerial connects to the chip). Encasing the chip in something like hot glue will help prevent the antenna detaching. For what it’s worth, the aerial in the card is about 13cm with 5 loops long but you may need to experiment a little to make a working replica.


Sun 20 Mar 2011 01:35:52 UTCSun 20 Mar 2011 01:40:50 UTCSun 20 Mar 2011 01:49:58 UTCSun 20 Mar 2011 04:43:48 UTCSun 20 Mar 2011 22:21:58 UTC

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Shinkutanku; Japanese for “Think Tank”. A very infrequently updated blog by your average code-monkey cum photographer.

Twitter: @CiaranEaton