Dont let your Mac fall asleep.
With a mouse clic, I can prevent my Mac from going to sleep, until I deactivate the feature. Very useful when doing presentations (avoid lock screen and screensavers when you're talking too long).
A word about the UX: it's dead simple (two states, on and off) and beautiful. Great work.
Get it here, it's free.
Share. Files. Fast.
CloudApp allows you to share images, links, music, videos and files. Here is how it works: choose a file, drag it to the menubar and let it take care of the rest. You get a short link automatically copied to your clipboard that you can use to share your upload.
It has a "auto-upload screenshot" which I use all the time. Just take a screenshot, and you immediately get a link to the image online.
Get it here, basic plan is free.
Listening to Grooveshark or Deezer all day and fed up with having to leave a tab with the site open and going back and forth to this tab to see/change/stop/forward/pause your music? omPlayer at the rescue.
omPlayer is a special minimalist web browser to comfortably listen to music from online music services. For supported services it lets you control playback from menu bar or from any application with global shortcuts and media keys, supports Growl / Notification Center notifications and Last.fm scrobbling.
Currently supported services: Google Play Music, Grooveshark, Pandora, Deezer.
Get it here for $1.99. Worth it.
QuickHub is a tiny but useful OS X application for GitHub lovers. It helps you to quickly access to GitHub directly from your status bar: Repositories, issues, gists, pull requests, users, organizations and watched repos are just one click away. QuickHub also provides Gists creation feature and will notify you when something changes on your GitHub artifacts.
I use it mainly to access my Gists quickly, really handy.
Get it here for $0.99 / 0.79€.
Reader Notifier allows you to be notified in the notification center of new items in your Google Reader account. I use it to follow the Hacker News feed live.
NB: I don't know what will happen when Google Reader will shutdown :-(
Get in on the Mac App Store, it's free.