Using a mini-monitor for Photoshop toolbars or tracking email is pretty handy, but they're also pricey. DoubleSight's new 7- and 9-inch LCDs aren't touchscreen, but I like that they start at just $US120.
That price gets you the 7-incher, which has a resolution of 800 x 480. The 9-inch models ($US160 with detachable webcam; $US140 without) can do 1024 by 600. Each uses USB for both video and power — you don't need any fancy graphics card.
What sells me on them, though: they'll also pivot between landscape and portrait orientations. Nice. [DoubleSight]