Vacuum

Two quick ideas for vacuum cleaners.
<accent type="british">Ones that work properly.</accent>

Cordless Upright Vacuum
This one, I could build. I'm tempted to. Get me an off-the-shelf energy-star vacuum cleaner, a home office uninterruptible power supply, some warranty-voiding tools, a few yards of duct tape, and an afternoon, and I'll give you a vacuum that doesn't try to trip you dozens of times with its big stupid clumsy power cord while you use it. Actually I won't give it to you, I'll keep it. Even if it kind of sucks.
(...Did a quick Google search... no, not a little pretend vacuum, not a dustbuster, a real friggin' cordless vacuum. I don't care if it's heavy. I'm as strong as I am clumsy. Lose the wire.)

Spot RoomBot
We don't have a roomba, but the idea is appealing. We do, however, have a spotbot, and it is worth its weight in gold because it cleans up after our runt of a cat, who can't eat anything other than one kind of prescription food, but does anyway. A spotbot which could seek out the next area of barfplops and tailsmears would be worth its weight in ... something else super-valuable.
...This one's quite a bit harder. It would need to be able to refuel itself with water and detergent (and dump out the cat-barf-tainted water) as well as deal with taller solid masses in addition to spill-type floor-level stains. Sign me up for version 2.0 of this one; working out the kinks in this design would be more gross than my current techniques.

Prior Art

One of the memes buzzing around the hippie geek community lately is a way to stick it to those greedy corporations who think they can own math and such, and who bully everybody with patent infringement lawsuit threats and backroom licensing agreements. How? By brain-dumping ideas publicly. If proof exists of prior art or even that an idea has been published, a patent on it can be struck down.

I don't have any brilliant ideas, but i have some mundane ones that are much more clever than half the crap that gets awarded patents these days. So here they are, at least the ones I can remember off the top of my head, and if any greedy corporation is reading, go ahead and make these things happen, but you can't have patents on 'em. Not for long anyway. They're braindead ideas, documented here as prior art.

Video Projector With Smart Auto-Adjust
Implementation 1: Infrared beacons or reflective tape is built-in or can be attached to all 4 corners of any reflective screen, a small infrared camera in the projector (much like the one in a Wii controller) detects the positions of the screen corners, and software distorts and adjusts the projected image to be the correct shape and size.
Implementation 2: No beacons, but a small camera built into the projector feeds data to software that scans for a big, bright, 4-sided polygon, and adjusts the projected image. Probably the better implementation for most cases. A single unit could be capable of using both methods.

Product Placement in Photo/Video/Art Sharing Sites
My friend's Flickr account contains a photo of someone clearly holding a branded pop can. He deserves ad revenue-per-view as much as advertising agencies do. Better yet, pay individuals for stuff like this and stop polluting broadcast and print media with loud and obnoxious ads.

Non-Fling Fingernail Clipper
The otherwise-standard clipper has a soft, spongy clamp behind the blades, which holds a clipped nail until released, rather than ejecting it at a random, high-velocity trajectory.

Pi Compression
(see earlier post)

AI-Engineered Codecs
(see earlier post)