Comment Carry Only What You Need (Score 1) 763
If your goal is to ensure that you are able to get back home, why bother having all those keys with you? It's time to break up your keys into several groups. After all, you have multiple directories for all the files on your system, so why not gorup the keys?
You'll need the two keys for your own doors, plus a key for the vehicle you need. You can leave the knife, keys to your girlfriend's, etc. in your backpack.
I personally carry around four keys, which easily fits in my pocket -- two for my bike (my main mode of transportation), one for the gate, and one for the apartment door. I have a mail key, but that never leaves the apartment. I also have keys to my (separated) parents' places, but they're stored in a secure location in my home unless I need them.