Fancy video flat panels seem to be hanging in every office and corner tavern. But for a really big flat picture (10 feet wide or more) a projector is the state of the art. Business projectors are becoming everyday tools for video and data presentations, in boardrooms and on sales calls. Today's portables travel well, and in the office a projected image can capture an audience. Beyond price and size, you can compare projectors by their brightness, contrast, and resolution (see below). Meanwhile, they keep shrinking. Susan Myers, director of research at THT Research, says projector technology may soon land in cell phones.

Spec sheet Several measurements reflect a projector's image quality, including these:

Lumens: A wide range is acceptable for this measure of brightness. Business projectors generally are between 1,000 and 5,000 lumens. A theater-quality model may top 10,000.

Contrast ratio: A comparison between brightness of whites and blacks. Numbers can vary widely without vast visible differences. Business projectors range from 1,000:1 to 5,000:1.

Resolution: Projectors to be used with computers should support at least 1,024 by 768 resolution. Full high-definition video projectors are 1,920 by 1,080.

Best for...Outfitting the conference room

What it is: A sleek large-venue projector

What's cool: The VPL-FX40 delivers an image that's crisp and sharp, and its ample brightness (4,000 lumens) lets it work in a room with a fairly large amount of ambient light--perfect for making presentations to note takers who like to be able to see what they're writing. It offers a wide range of digital and video inputs, and it can also be installed directly on your network to project presentations from any computer in the office.

Drawbacks: Some gadget hounds grumble that a high-definition image resolution might have been nice for the VPL-FX40's steep price.

Price: $4,500 to $5,000

Best for...Impressing an auditorium crowd

What it is: A high-definition large-venue projector loaded with features

What's cool: The PT-DW10000U offers spectacular image quality, and it's one of the most compact projectors in its class. It beams 10,000 lumens of brightness (hence the name) and has a high, 5,000:1 contrast ratio. With high-definition resolution of up to 1,920 by 1,080, it will project an image wider than 10 feet without a problem.

The unit's automated filter cleaning frees you from that chore until after 2,000 hours of use--which could be years.

Drawbacks: The price (see below)

Price: $59,000

Best for...Presentations on the go

What it is: A lightweight (3.5 pounds) portable projector

What's cool: The NP60 is bright for a projector of its size, with a sleek design and a soft black carrying case. The brightness (3,000 lumens) means it holds up well in big conference rooms and rooms with high ambient light. The projector starts up the moment it's plugged in, automatically detects and optimizes input signals, and corrects focus and image shape on the fly.

Drawbacks: Unless you use the projector in its lamp-life-extending "Eco mode," the fan noise can be loud.

Price: About $1,300

Best for...Saving money

What it is: A 6.4-pound portable projector with a wide range of connectivity options

What's cool: Budget-minded buyers need to think hard about priorities. Is brightness more important than accurate color reproduction? Is greater connectivity worth a couple of extra pounds? The XR-30X, released in June to replace the popular XR-10X model, is a versatile projector that performs well with both text and graphical displays and is bright enough to handle a fair amount of ambient light. Inputs handle a variety of video and digital connections, making the projector a good fit for a collaborative meeting place.

Drawbacks: At 2,300 lumens, it trades some brightness for mobility.

Price: About $800

Best for...Keeping your suitcase light

What it is: A pocket-sized battery-powered projector that weighs just over a pound

What's cool: One of the lightest and smallest projectors on the market, the TDP-FF1AU fits quite literally in the palm of your hand, and also comes with a foldable 23-inch projection screen. A small remote control handles most basic operations, and the detachable rechargeable battery gives you two hours of run time. And thanks to a USB port--rare among projectors of its size--you can simply turn it on, plug in your presentation, and go.

Drawbacks: Because of its size, it isn't nearly as bright as traditional projectors, so it can't handle large conference rooms.

Price: About $700

Best for...Watching the latest flicks after work

What it is: A high-definition projector for home theater use that can handle business presentations

What's cool: There's frequently a tradeoff between the brightness business users need and the good contrast and color consumers want for watching movies. The PowerLite 1080 goes a long way toward resolving that dilemma. Its high-definition video inputs and vivid colors make it dazzle in a living room, and it stands up well to business presentations in environments where there's not excessive ambient light.

Drawbacks: It's heavy--just over 12 pounds--so you won't want to lug the PowerLite back and forth often.

Price: About $3,000