Which apps help you work more productively in OS X?
nvALT + Simplenote
Notational Velocity has become my preferred note-taking application after ditching Evernote (I now use Evernote as a clipping tool/stash). nvALT supports Dropbox and Simplenote, and the synchronisation with Simplenote has become a blessing. My notes are accesible across all of my devices and online through the Simplenote interface. What makes nvALT so special is that it is extremely lightweight, meets its purpose perfectly, and has basic note formatting.
I also depend heavily on Alfred and Dropbox for my everyday needs. Right now I'm looking for an app that assimilate Windows' window-snapping feature. Suggestions?