Discard this idea if you're looking for quick identification with the requirement of some memorization (i.e. colors).  

Personally, I use a metal engraver from Amazon (roughly $14) and write something on the key.  I use an acronym (SR = Snowboard Rack) or a name/word (Dad = Dad's house).  The benefit of this is that you can be descriptive, but the downside is that you will need to take a close look at your keys.