ImageWell rocks for quick and easy edits to images. Just drag an image onto the well, make your adjustments (like cropping, rotating, watermarking and/or resizing) and send the file to the local folder, FTP server or iDisk of your choice. It supports .Mac, WebDAV, FTP and SFTP for uploads. A few simple clicks is all it takes and you'll generally be done with what you needed to do in about the same amount of time it would take for Photoshop to even launch. You can even add text, shapes, thought clouds and balloons with ease without having to launch another app to dress up your pic.
Although the basic application is free, ImageWell now also offers a registered version that includes some additional bells and whistles, like more shapes, styles, gradients, and batch resizing. You can upgrade to the registered version for $9.95 during the v3 beta, but the regular price will be $14.95.
The interface on ImageWell 3 is a bit different than version 2.x. (no more drawers!) and I was a tad confused by that when I launched it - I'm quite the creature of habit. But once I figured out where things had moved to I felt at ease again. The online help and documentation is very good. though, so if you're confused too, just fire up the help pages and you'll be all set.
ImageWell 3 requires OS X 10.3.9 or greater, and is a Universal Binary. If you're looking for a lean and mean image editor, give it a try.