Last summer, I somehow lost DH's keys. I put them into the mailbox down the street to get our mail, and forgot to remove them from the box. When we realized they were missing, the keys were gone. Thankfully, we had extra truck keys -- but we realized it would be pretty easy to figure out whose house the keys belonged to so we had to change our front door lock.
We chose to replace our deadbolt with a touchpad keyless deadbolt and I have LOVED it ever since! (the link isn't to the one we have - but it's just like it.) I don't have to struggle with my keys to get in the front door. The boys both know the code (and also to keep it secret), so they can unlock the door for me when we come home. It's a simple push button from the outside to lock it. There's no chance of getting locked out by accident -- since you don't need keys!
The only thing I wish ours had was a glow panel, but the few times I've been stuck in the dark I've used my cell phone to shed light on the numbers.
A key still works as backup, so I keep one on my keyring in case the batteries go dead (although we changed them this summer - just in case!)
It didn't cost that much more than a traditional deadbolt, and it has made our lives much easier! Sometimes it's the simplest things that make life easier.