I'm working on a post about how best to use human memory—when it's good to store things in your own brain and why, when it's best to outsource your memory, what memory upgrades are worthwhile in what contexts, and how to integrate and apply memory systems in real life. I'm hoping the following set of memory problems will draw out approaches that haven't occurred to me so I can compare a wider range of methods.

I'll post the first solutions I thought of myself later on, but for now I'd like to hear what you would do in each of these situations and what you believe to be the pros and cons of your answers. Can you think of ways to improve upon your first thoughts and the answers of others?

(You don't have to respond to all of the questions; feel free to post as little or as much as comes to mind.)

1. I'm leaving for a week-long business trip. The last time this happened, I wasn't totally sure I'd remembered to lock my door. The worry wouldn't leave my mind and was making it hard to relax, so I eventually called a friend and asked them to stop by and make sure it was locked. Now, I'm standing in front of my door, suitcase in hand, all ready to go, and I'm about to lock it. What should I do?

2. I'm in the middle of a conversation with a friend. He mentions a book that really interests me. It's called Antifragile and I think, "I've got to remember to Google that." But the conversation continues, and it would be rude to pull out my phone right this minute.

3. I bought a new fridge. This one closes differently than my old fridge: My old fridge would swing shut and seal nicely if I just left it open, while this one requires that I push on the door even when it's mostly closed to ensure it seals. For some reason, I'm having a hard time with this transition. I've had it for a week, and I've come home from work to find my more perishable food spoiled three times already. It's not that there's a problem with the latching mechanism or that the seal is bad. The problem is that I keep forgetting.

4. I'm driving in an unfamiliar city. My GPS says my destination is somewhere around here, but I suspect it's working with slightly outdated information. Rather than driving around aimlessly in hopes that I'll randomly run across that which I seek, I sensibly stop to ask a local for directions. Unfortunately, it seems that the business I'm looking for has moved to another part of the city, and I'm going to have to remember more than seven things to get there.

5. I'm preparing a talk for an upcoming conference. It's not the kind of thing that would benefit much from a Power Point, so using one would be tacky. I don't care for the idea of flipping through note cards as I go either. And I definitely don't want to memorize an entire speech word-for-word. But neither do I want to just wing it and hope it turns out well-structured and non-rambly, and I'm afraid I'll forget one of the key points if I get nervous.

6. I've just started at a new school. I've been through this before, so I know that in the next two weeks I'm going to have to say or write my student ID number about a zillion times, after which point I'll still need it, but only occasionally. It's 12 digits long: 000458789625. I'll surely have it memorized by the end of the first two weeks just because I've repeated it so much, but it sure would be nice to not have to pull out my wallet, find my ID, switch my attention back and forth between that and what I'm writing, and then double check. Every damn time.

7. In an attempt to reduce stress, I'm trying to maintain a clear boundary between home and work by not working while I'm at home. But almost every evening, I think of several things related to work that I really want to remember. It's the worst when this happens as I'm trying to fall asleep, all snugly under the covers, and I don't even want to open my eyes to enter the thought into my phone, let alone to turn on a light, find my calendar, and pencil in a deadline.

8. This evening, I'll be going to a large and crowded party where my main goal is networking. I know of several important people who will be there (and whose favor I'd very much like to gain), and I know there will be dozens more I've never heard of with whom it will be useful to connect. But I'm getting anxious, because I'm terrible with names, and I don't want to make a fool of myself by forgetting something like which major startups one of the known important people has been funding.

9. I'm studying for the medical licensing exam. This basically means somehow turning myself into an encyclopedia of modern medicine. It's a giant mess of mostly disconnected facts, weird jargon, and lengthy procedures. I cannot even imagine fitting all of this into a single brain. I stare blankly at the table of contents of a 700 page textbook, and I begin to panic.