Two ideas have been bouncing around my head lately:

Top Loading Tumble Washer

Front loading washers are more efficient because they can tumble the clothes around in a spinning drum, Top loading washers are easier to make because they don't have a front door to keep sealed. So why not make a top loading tumble washer? The spinning drum has a door you can open, and you get at it by opening the top of the washer. You'd need something to orient the drum with it's door facing the top of the washer, but this doesn't sound too hard. This doesn't totally get around the problem of needing to make a good seal, but because the seal is no longer between a moving part and a still part it should be a lot simpler.

Magnetic Headphone Connection

I like the design of the mac book power connector. It holds itself in with magnets, so it pops out under force instead of pulling the computer onto the floor. I think headphones should work the same way. When I walk away from my computer without realizing my earbuds are still on, I get an unpleasant feeling as they pull themselves out of my ears. Headphone jacks are too standardized to change, but you could make a little connector that goes in the middle of the headphone cable that separates under force. Magnets to get a good connection, then if you make a small yank, it comes apart at the cable instead of your ears.