Running an air purifier on a battery could be really useful in an emergency that combined a biological or nuclear threat with a power outage. Getting one that can run on 12V DC and attaching it to a LiFePO4 battery is about $188 (plus $164 for the purifier) for something that will give you 141 CFM for over a week.

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I've been thinking about DIY biohardening, primarily to reduce risks from environment-to-human threats, and a lot of what's out there assumes the power grid stays up. This doesn't seem like a good assumption: even if society does a fantastic job protecting essential workers and prioritizing keeping the grid up, I expect many more outages than we have today, and longer ones. If an outage means you lose positive pressure and get sick, that's really very bad!

Most rooftop solar installs don't provide power when the grid is down. The primary goal is to avoid sending power out to the grid where it could injure people working to restore power, but more recently it's been expanded to avoid energized lines extending out from the panel where they could injure a firefighter on the roof. When we installed solar in 2018 we selected an inverter which offers an outlet that provides best-effort power ("Secure Power Supply") during grid outages when the sun is shining. I'd try to sell you on it, but the newer rules mean my inverter wouldn't be legal for a new install.

I suspect this doesn't pass a cost-benefit test, especially when you consider the risk of serious disasters. Since the harms of allowing it are concentrated (firefighters) while the benefits are diffuse (everyone with solar) and speculative (very uncommon for a disaster to be this serious), however, it got banned.

Still, I wanted to make sure mine was still working, and especially that it would be able to charge my two portable power stations (Anker SOLIX C1000 Gen1 and Gen2). I tried over the weekend, but it was cloudy and the panels weren't producing much. It wouldn't charge the batteries, but it could do an 8W lightbulb:

When Lily was about two she told me she wanted a song about "no". This was ten years ago, and I don't remember why she wanted this, but I made something up:

This is a song about no.
This is a song about no.
This is a song about no, no, no.
This is a song about no.

The song goes... No no no no no no no no no.
The song goes... No no no no no no no no no.
The song goes... No no no no no no no no no, no, no.
This is a song about no.

It's useful anytime the kids want a song about something I don't know a song about. For example, it often served as a song about "turtle". Of course the more syllables the subject has the harder it is to sing, but that just makes it more fun.

My older two kids (12y, 10y) like contra dancing, but but have been increasingly unhappy with the available opportunities: a family dance is "too boring", and BIDA is "not enough kids my age". What they wanted was a regular dance, but just kids. So we had one!

Ghiblified for privacy

We invited people ages 9-13: I really wanted to keep the age range narrow so the kids got the feeling of dancing with people their own age. I set up a spot for parents to hang out in another room, or they were welcome to drop off and head out. The lower age limit meant Nora (nearly 5) was watching from the sidelines, and a few other younger siblings stayed home. I did allow two 8yo younger siblings who can hold their own at a regular evening dance.

I like my far-UVC Aerolamp a lot, but haven't been using it much: each time I wanted to get it out I needed to put it up on a tall stand, and ensure it wasn't going to get knocked over. This evening I attached it to the wall, which is great:

Julia and I had been giving half since 2014, but in 2025 we drew on our savings to donate 81%. It looks to us like we're in a critical window for keeping the introduction of very powerful AI systems from being disastrous, and we want to do what we can while we still can.

Here's what that looks like in the context of our overall spending: