have you ever tried to reposition a firefox or chrome window that is full of tabs?

what happens when the window manager uses BeOS style titlebars?

what happens to my webex/remote-desktop overlays when there is no empty space for them to live over?

somewhat related: have you ever tried to resize a window that does not have obvious resize control handles? or have you ever tried to *not* resize a window when the non-obvious control 'areas' take your click instead of the drag-to-select-text that you intended?

and don't get me started on scrollbars that appear and disappear depending on where you put your cursor instead of what the content is.

take a look at the green eye from brultech, or a less-capable unit from smart energy groups. if you want more of a do-it-yourself kit try the hardware (and software) from openenergymonitor.org. there are many power monitor systems on the market, but imho these three are making the most progress for the home/maker market.

pedestrians simply walk around the roundabout (in either direction) until they reach the desired street. a crosswalk at each street that enters the roundabout (where incoming traffic must stop or yield anyway) makes this obvious.

is that a calculator that you hang around your neck? :)

i imagine a set of 'wifi-vision goggles' or, more generally, non-visible electro-magnetic spectrum goggles. when you look through the goggles, you see the normal world with overlays of different colors representing different parts of the non-visible (to humans) electromagnetic spectrum, with the brightness proportional to the signal strength.

if 3d edge detection is possible, then render a surface as well.

you could filter individual wifi channels, or filter for other bands such as vhf/uhf television, am/fm radio frequencies, microwave ovens, etc.

alas, too many projects and not enough time.