I am a beginner when it comes to writing desktop applications, but here are two that I have created for Mac OS X. Not guaranteeing stability or reliability for any of them.

• ScreenGrab (Download)

Upload screenshots taken by the built in Mac OS X screenshot feature directly to an FTP server and have URL copied right to clipboard for quick sharing. Built off the concept of the original GrabUp software that no longer exists. ScreenGrab is for Mac OS X Snow Leopard only.

• Pasteinator (Download)

Publish large pieces of text to Pastebin.com and Pasteinator.com right from your desktop rather than opening a new browser window. Works on both Mac OS X Leopard and Mac OS X Snow Leopard.
Update: Pastebin.com was bought out and is no longer compatible with Pasteinator. No plans are made to make it work again.