Agreed, the Kastle is great fun. (I got mine prebuilt and it was still damn cheap.) Limited in scope, but you can do some surprisingly cool West Coast synthesis stuff with it, like the self-playing Krell Patch.
(And it’s ridiculously tiny… like no matter how many things you read online saying how tiny it is, it doesn’t sink in until you open the box and exclaim “holy shit, this thing is tiny.”)
It works well with an actual modular system too. It doesn’t track 1V/octave, but you can reset the LFO in sync with triggers/clocks, and it sounds pretty amazing through an LPG. And it also plays nicely with a breadboard to give some more space to add stuff if you’re so inclined.
Another recommendation for a couple of notches up in price, but freaking amazing, is the Make Noise 0-Coast. It’s a really lovely instrument and costs about 1/3 of what you’d pay to build a similar (but not identical) Eurorack setup.
