topton is one of the more “trusted” brands in there. you can get anything from a small dual core celeron to a mobile i7, with two ddr5 slots, m.2 slots, mpcie slots, sata slots… you name it.

it can be quite a punch on a tiny box and it is a very practical all-in-one device, but it does need some tinkering repasting and adjusting out of the box. mine in particular has issues around wol and absolutely needed cooling fans and better thermal paste. ymmv.

here is a popular one.

here is some discussion about these boxes with varying levels of success in using it, its quite good once the kinks are worked out.

this form factor is definetly something if you want a homelab without the hassle, pricetag, size, noise, energy consumption… you can virtualize everything in it if you get one big enough.