Mac: Pomodorable is the perfect Pomodoro timer and to-do tracker. It uses visual cues to keep you organised and on track, and integrates completely with Reminders in OS X Mountain Lion. Change a to-do in Pomodorable, and it's immediately synced to Reminders.
Fans of the Pomodoro Technique know a good timer is important to stay on task. Pomodorable ditches the traditional countdown timer in favour of an card on your desktop that displays the item you're scheduled to work on. As the clock ticks, the tomato on top of the card grows from a baby green tomato to a ripe, red one with full vines. When the tomato is plump and the alert sounds, it's time to take a break.
In addition to Reminders integration, Pomodorable also syncs with to-do managers OmniFocus and Things. Your next actions are always in the menubar, and you can control the app from there without having to open those other apps. If you're tired of traditional countdown Pomodoro timers, Pomodorable is worth a look. It will set you back $5.49 in the Mac App Store (for a limited time -- regular price is $10.49.)