Mac OS X: Quicksilver has long been a favoured application launcher for Mac users who want ultra-customised keyboard control. While active development ceased for quite a few years, activity resumed last year and has continued apace, with version ß59 hitting servers last week.
File syncing tool Dropbox is one of our favourite tools for sharing files over the internet. Instead of opening your browser to find the public link to a file, though, you can copy it to your clipboard instantaneously with a Quicksilver action.