I generally carry two knives on me at a time. My old stand-bys have been a benchmade tanto, and a leatherman. Over the last few months I've been carrying a Cold Steel American Lawman on my main hand and a Benchmade Rukus for the off-hand mainly bc it's easier to open w/ my left hand.
As far as california law is concerned I have found them to be ambiguous. There isn't really a length limit for folders, but they need to stay open when they're open and stay closed when they're closed. Fixed blades are only permitted if they fit the context of the situation (i.e. camping, hiking, etc.). The machete will have to wait at home while you go to the grocery store.