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If you do want to give amateur radio satellites and/or cubesats a shot, there's a whole bunch of these that transmit a bunch of different stuff. Most of them transmit telemetry, or amateur radio stuff, but I know there have been a few that have transmitted SSTV images or even pictures from onboard cameras. Satnogs is a great resource for these spacecraft, since they have an excellent database and a forum full of info. I've always used gr-satellites, which is part of the GNU Radio ecosystem, to receive these satellites. Fair warning, though, these satellites can be a bit tricky to work with. For one, GNU Radio isn't always the most beginner-friendly software to get set up. And some of these satellites, especially the cubesats, just don't have the strongest of signals.
Also, as u/Antenna101 mentioned, dead satellites can be fun to hunt for. Of course, you won't be receiving any useful data or images with these. And whether or not they transmit anything can be pretty hit or miss. But some of them, like Transit 5B-5, transmit some interesting signals when they do show up. Here's a list of several dead satellites, if you're interested.