The old IBM model Ms were often washed in a dishwasher - don't use soap, but hot water cleaned them out. Most circuit boards are (or were - I haven't looked in 20 years) washed in hot water near the end of their assembly. Just air dry for a day before use. Ideally you should was in deionized water (or at least rinse with distilled), but if you don't do this often most regular tap water is good enough)

The old model M's also had easy to replace keycaps so you could take them off and wash as often as you want. Only downside is the need to put them back on in the right place each time, which is tedious.

Not all electronic components are water safe, but most are. I have no idea how you figure out if your device is or not without taking it apart. If you do this "often" expect that screws will rust, or minerals will build up - each causing problems. However if you just wash once a year you can get a lot of junk out.

I dishwash my keyboards (Kinesis contoured) every year or so. Just rinse thoroughly, don't use high-temperature drying, and wait for it dry completely before powering on.

I have put multiple cheaper keyboards through the dishwasher over the years. No heat, no soap, and I make sure to thoroughly dry it of course. I wouldn't do it with a mechanical keyboard for obvious reasons, but I have done it many times with membrane keyboards.

I suspect the Model M was dishwasher safe (if you popped off the keycaps so they don't get lost - put them in a separate dishwasher bag). ... and there's a fair bit of material out there of people trying some variation of it.

Didnt the TV shop have a rolling keyboard?

Plug the ending of the usb somehow (3d printed part?) and it would work?