Things you can run out of while looking for your missing cat:

• fliers
• tape
• staples (once you've upgraded from packing tape to a brand new staple gun)
• energy (for asking strangers if they've seen the cat and then talking with them about how you miss her)
• breath (for playing the ocarina she loves)
• will-power (to keep singing the song from when she was a tiny kitten about how you love her and miss her when she's gone)