Good for... True Portability

The compact 1.5-pound Printstik can spit out boarding passes or important e-mails, and it can handle the graphics in webpages and PowerPoints (though not in color). You don't have to be near an outlet, either; it can print up to 30 pages on a charge. The Printstik works not only with laptops but also with BlackBerrys, if you get the model with a built-in Bluetooth connection.
Cost: $200 without Bluetooth; $300 with Bluetooth; $350 for a higher-resolution model

Good for... Printing High-Quality Documents and Photos

At 4.4 pounds, the Canon PIXMA iP100 is heftier than the Printstik, but it can print in color, offers higher resolution for black-and-white documents, and is much faster (20 pages per minute versus three). It can also print a 4-by-6 photo in 50 seconds. Convenient accessories include a $50 Bluetooth adapter for use with mobile phones, a $90 car charger, and a $100 battery that delivers 290 pages on a charge.
Cost: $250

Good for... Printing From your iPhone

Don't feel like carrying a printer around? You can still print your pics with the free HP iPrint Photo application for the iPhone. The app works with most Wi-Fi -- enabled ink-jet printers from HP.