This is a very personal list.

• Playing the same pieces on the same piano that my grandfather once played: a baby grand in the house that my grandmother is now selling. My piano abilities are on the low end of mediocre, and he's been dead for twenty years, but I long to connect with him in music before my chance is lost forever.
• Keeping two healthy and affectionate fancy rats of my own. I couldn't do it the last time I tried; I returned the rats to the pet store. But every time I see a picture of a rat, I long to have them again.