Thanks Viper, good point!
I'm now moving towards trying something out. I'm just waiting for a package to land from DX, which will allow me to be a little more flexible, though with far greater redundancy. I've realised I have a humongous amount of keys for various different things, but don't always carry everything all at the same time.
I'm going to break them all down into home, work, car, boat, boatyard etc and aim for getting a small blade, a bottle opener, a mini lighter, and a fauxton type light on each cluster so no matter where I am or which bunch I happen to be carrying, I'll have the basics. The truth is that all these are excellent little tools so it makes sense to split them all up and increase the chances of having access to one or another. I'm also going to be tagging a fauxton onto my most carried SAK's. I know it might seem like over kill, but I have been in situations where having several lights really saved the day.
The Alox Rambler is the exception though. That won't be going on a key chain, it will be paired with a shiny light from 4sevens for those lightweight days. The PTC, utilikey & manager will be split up between home, car and work keys as these are the most frequently carried (unfortunately

)