These are free. Put together a plan, and have at it. Don't hurt yourselves. Much.
The advantage of a strong hybrid (or even a weak hybrid) is that energy expended during stopping can be recovered and used to accelerate. So hybrids would be most effective in slow moving, stop and go vehicles. That is primarily how the US Postal Service vehicles are used. Hybrids should be able to double their miles/gallon.
The trucks are custom, with their own service fleet, and return home every night. There are thousands of the vehicles, conversion would be straight forward. They look like they have plenty of room inside. This is the kind of closed form experiment that could work out.
The USPS is under pressure to reduce costs. This would be flashy and green.
Infrared sensors allow the user to "see" objects generating heat using visual methods, but the current implementation using vision, is less than ideal. When thermal displays are used, goggles obscure normal vision, and separate displays cannot be used s unless the operator constantly stares at the screen - generally a bad idea.
I propose building a vest or belt, that will have vibrators on it, which vibrate based on the heat sense from a particular direction. It is based on the functional success of a similar concept for magnetic heading. After some training, the user should be able to associate the heat signature of a person, a car, a discharged weapon, by matching the visual with the thermal perception.
Vibrators would be a problem due to battery power. Perhaps some linear motors that press into the skin to indicate intensity? Thermal bandwidths are pretty low, so they would not have to be fast. Perhaps slight currents through the skin, proportional to the thermal profile sensed would give you enough of a tingle to learn and recognize thermal signatures?
This would not be very useful in very busy thermal environments (like a sports bar). It would be very effective if seeking animals in the woods, or sizing up parked cars (is someone hiding in the back? Which ones have been recently driven/are running?) or detecting if someone is waiting out of sight, or is approaching you from behind.
This would also be very helpful to the blind, allowing them to be aware of objects in the general vicinity without touching them. For instance, a doorbell could include an infrared pulsing device, to enable more exact location of the device.
The power of this concept is that a user can sense the relative changes in the thermal profiles as they move their head or limbs, providing very precise location capabilities. This is how snakes do it, and they strike prey in total darkness.
Update, 2014: Here is something like it...Vibrating Clothes.
Combat soldiers have personal communicators, that have trouble working in and around buildings. I propose that the communication repeaters be adapted to ac power lines - where ever there are multistory buildings, there is usually electrical wiring. These would be battery powered, and plug into the outlets in the building. A pair (or more) will use the wiring as a signal distribution network. This is based on Broadband over Powerlines (BPL) technology, which is common and very inexpensive. Of course, in a military situation, the normally very low power limits for use of this equipment during peacetime do not apply. The signal can be very robust. A unit would consist of a wireless interface, a network processor, a battery, and a BPL interface. They would be hand carried, and disposable/recoverable.
In this game, Augmented Reality is used on Android or iPhones to overlay game tasks and goals over the real world. By looking at the phone, it becomes a viewport into another world, overlaid on the real world. So to get something 20 feet away, you would have to walk 20 feet. Virtual demons could swoop down on you, and you would have to duck. Given the camera function, you may even be able to use terrain and other features as part of the game. We came up with this in the 80s, but did not have the technology to execute it.
As an action game, it would probably be too hazardous. But a simple game of hide and seek may work pretty well. How about a game to cross an area by jumping onto circles that appear and disappear at regular intervals? Frogger with real people. Use game theory to take it from there.
Most train crossings do not have gates or lighted warnings, there are just too many to bear the cost of the infrastructure. So how about using cellular technology to transmit that a train is approaching a crossing?
A sensor is mounted some distance from the crossing to detect a train, probably using sound or vibration sensors. It transmits that a train is approaching a crossing to the local cellular tower, which then forwards the warning to locally registered phones (this is known, the cell tower must know this to ring your phone or forward you a message). In your phone, your local application detects you are traveling toward a crossing, and you get a warning.
The warning messaging technology is in use now (for floods, tornadoes, etc). The train sensors would be no more complex than an unmanned cellular phone, which use so little power they can be solar powered. A stand alone track side install, no wires needed, that triggers on ground vibrations caused by the approaching train, and transmits to the local tower. Way cheaper than automatic crossing gates. Hardware would be inexpensive, basically a low end cellular phone without a display, and a solar cell. Very large quantities, about 7000 in Iowa, for example. Simple installation, straightforward redundancy - just mount two or more.