A Swiss Army Traveler has gone everywhere I have for 40 years. It's supplemented by a fully serrated Spyderco Delica in the other pocket for jobs a plain edge can't handle. I have many others, but they stay home most days.
Bought 3 of these Spyderco Tim Wegner folders on Ebay after they were discontinued for around $60-65 each(retail was around $165). I've been carrying one everyday for about 15-16 years. Lost one somewhere and one needs to be sent back to Spyderco to be refurbished. Absolutely love them!
I carry a Lightning Double Action Out The Front Automatic Knife. Fast and easy to open and close, can be done without drawing attention to you even opening. Only need to use your thumb to open and close.