First a general suggestion: search every-day carry (EDC) sites (like [EDC][1] or [EDC Forums][2]. Forums][2]). You will find posts and pictures of almost any possible item that can be used as a keychain. My personal solution (at the moment) is a [split ring][3] and [clips][4] from County Comm.
[1]: http://everyday-carry.com/archive
[2]: http://edcforums.com/
[3]: http://www.countycomm.com/tisplitring.html
[4]: http://www.countycomm.com/flatgateclip.html