By Becky Waring

Mobile warriors weary of lugging around projectors for presentations may soon be able to unload their burden. Revolutionary palm-sized "pico" projectors are coming that will make it easy for anyone to take their show on the road.

Most make use of LEDs, rather than bulbs, making them cool, long-lasting, energy-efficient and sturdy enough to carry in your pocket. Light output is far smaller than with conventional projectors, about 100 lumens, so you'll need a darkened room, but they should work fine for small groups and casual viewing. Brightness should improve quickly as the technology matures.

While tantalizing glimpses of these tiny projectors (some even built right into cell phones!) have been appearing for almost two years in Japan and at various electronics shows, they are finally ready for the public domain, with products now available in the U.S.

One of the first out of the gate is the 3M Micro Professional Projector MPro110 ($359), which projects a 50-inch diagonal picture up to 640-by-480 pixels from its tiny 5.6-ounce body. It has both RCA (composite) and VGA video inputs, for compatibility with almost any computer or video device, such as camcorders and DVD players. A threaded mount lets you attach it to any standard tripod for stable positioning. The battery lasts up to one hour.

Next up is the Optoma Pico PK-101 ($400), a 4-ounce marvel that projects a standard definition NTSC or PAL image up to 60 inches. Listing for $400, the projector runs for about 2 hours on its battery and recharges over a USB cable from your laptop, a real convenience. The Optoma includes a tripod mount and cables for connecting to your iPhone or video iPod. It can also use a standard composite AV output from camcorders, DVD players and other video devices. Most laptops can also output composite video with an appropriate adapter.

The 3M and Optoma are pretty similar, since they are both based on Texas Instruments DLP technology. A third entry, coming this spring from Microvision, is code-named "Show." Based on the company's PicoP display module, Show will be capable of projecting an 848-by-480 WVGA image anywhere from 12 to 100 inches in size (depending on ambient lighting) and can run off its internal battery for up to 2.5 hours. It connects to your laptop or video-capable smartphone (such as the iPhone) with a standard video cable or adapter. The PicoP technology does not require lenses, so is always in focus at any distance. It will list for around $300.

We bet once you get used to the convenience of being able to project anywhere, you'll find all sorts of reasons to pull out your pocket wonder, such as showing those vacation pics or baby videos.

But watch out for even smaller pico projectors that will be built right into cell phones in the near future. While not high-quality enough for business presentations (at least at first!), they will be perfect for sharing that YouTube video or photo slide show with your friends on the go.