Picasa 2 (freeware)
On July 13, 2004, Google acquired Picasa. So you might have guessed the answer. Picasa is great at searching and organizing pictures stored everywhere in your machine. Picasa is tightly attached to other Google services(Gmail, Hello, Blogger). Picasa has a simple but florid user interface, and a bad support with GB2312.
IrfanView 3.95 (freeware)
Do you think your ACDSee 6.0 PowerPack is extremely slow? Although it is really more powerful than version 3.0, I just couldn’t bear its startup speed, slow like a snail. So if you were also hunting for a high-efficient image browser, you’d make a trial of IrfanView, which is on the top of my recommendation list. Believe it or not, its setup file size is only 856.5kB!
With various plugins, it can also handle text/audio/video files. This brings a shortcoming that you may find too much IrfanView icons(little red reptiles) in your computer.
Turbo Photo 4.2 (shareware)
It contains both an image editor and an image browser. I use Turbo Photo to resize images, enhance quality, and add personalized frames.