QuickStep is a fast, simple image viewer. It can read JPG, PNG, GIF, and TIFF images. It can locate and display images of those types within ZIP, RAR, and TAR archives. QuickStep can be started from the Finder but is also designed to work well when started from a terminal. It is keyboard friendly: most commands use single keystrokes instead of Command-key combinations. It can display images fullscreen and run a slideshow.
yaspi (Yosi's Anti-Spam POP3 fIlter bot) is a POP3 mail-scanner specifically made to combat mail bombings caused by viruses (i.e. Swen). It connects to the POP3 server, inspects the messages, and deletes the infected ones without ever downloading them. Its most interesting feature is that it can automatically send abuse reports to the ISPs from which the infected mails originated.
Cache 901 is an advanced paperless geocaching program, allowing easy maintenance of a large number of caches locally. It is especially designed to work well on netbooks, allowing them to be taken on the trail and provide any assistance that can be gotten from the data you store. This can include advanced searching capabilities, logs, photos, and personal notes for any cache.
OndeSoft Screen Capture expands on the simplistic screen capture function in Mac OS X by adding customization and editing features, including the ability to easily select multiple windows, copy entire windows with a single click, and multiple image editing tools perfect for users of any skill level.