If you're using Picasa you don't need to read any further, as I'm sure you already know this. If you're not using Picasa for any reason, let me tell you one of the main reasons I do. As you probably know Picasa is a pretty handy little free program for editing, managing and sharing your photos, but I rarely use it for any of those things. What I love most about Picasa is the included Picasa Photo Viewer application.
Picasa's Photo Viewer lets you quickly preview image files from your desktop or while navigating your hard drive or external storage. I find Photo Viewer to be quick and very convenient when it comes to previewing images, especially when compared to the Windows standard Picture & Fax viewer. Photo Viewer supports JPEG, TIF, GIF, BMP, TGA, PSD, and RAW images.
Photo Viewer allows me to quickly review dozens or even hundres of images, and I can zoom in, return to 1:1, email, print or even launch the image in another application. The program uses a "lightbox" effect to open the image in a layer over your desktop and other windows. (see example below)
If you reading this far, I'm assuming you haven't used Picasa, so as I mentioned briefly, the full program does do photo editing and other management tasks well too. Although I don't typically use it for anything other than the Photo Viewer, if you're anything like me you'll spend way too much time checking out all of its capabilities when you should be outside enjoying the beautiful weather this weekend! 😎