I keep getting asked for this link, so I’ll post it here so I don’t have to go and find it every time.
DIY: The 2-minute Stylus
http://howto.cnet.com/8301-11310_39-57398322-285/diy-the-2-minute-stylus/
Top tip, if you tuck a little of the silver foil into the pen barrel before you poke the cotton-wool bud into it you get a more reliable stylus.
Here’s one I made earlier:
From my blog: DIY iPhone/iPad stylus http://t.co/r28FT5t0