A Raspberry Pi sitting on a shelf at home, quietly handling network ad blocking, backups, uptime monitoring, and a long tail of small automations, for my clients and for me.
Running a consultancy on a laptop is fine until you realize the boring infrastructure jobs (backups, uptime monitoring, the network plumbing) should not depend on whether the laptop is open.
I needed a small, cheap, always-on box that could do the things SaaS would otherwise nickel-and-dime me for: monitor my clients' sites and tell me when they go down, run scheduled backups, block ads at the DNS level for my whole network, and give me a private mesh into my client environments without exposing anything to the public internet.
A Raspberry Pi 400 in a fanless case, behind a UPS, running a tight stack of self-hosted tools. Each service runs in its own systemd unit so failures stay isolated, and the whole thing pages me via ntfy when something doesn't come back up.
It's the dullest project on this list and the one I'm most quietly proud of. I know within minutes when a client site goes down. Backups happen whether I'm working or not. The ad blocking pays for itself in saved bandwidth every month. And when a friend asks me to fix their printer, I have a Tailscale node ready to drop into their network.
The temptation with home-lab work is to keep adding services. The discipline is to not. Every service on the box has to earn its place by replacing something I would otherwise pay for, or by enabling something I couldn't do otherwise. The eight running services are eight conscious decisions; everything else got cut.
Also: a $75 Raspberry Pi running for years is a really effective answer to a lot of consulting-overhead problems. Sometimes the right tool is not a SaaS subscription.