Click Notify, and at the scheduled time, your reminder appears--and an audible alert sounds--on all the selected devices. If you included your e-mail address as a destination for the notification, you also receive the e-mail reminder at the same time. No matter where you're at, or which of your computing gadgets you've got with you, you're sure to get your reminder. I tested Notificant with two Macs, an iPhone, and an iPad, and Notificant's reminders never failed to appear on the chosen devices.

Of course, Notificant needs to be running on your Mac(s) to receive and display your reminders, and each of your devices needs some sort of Internet connection to synchronize reminders. (The iOS version uses Apple's notification service, so the app doesn't need to be running on your iOS devices to receive messages.) However, you don't need an active Internet connection at the actual time of the reminder--Notificant will store reminders for later notification, so as long as a particular device has had an Internet connection you created a reminder, that reminder should go off on that device at the scheduled time.

Because of the 160-character message limit, Notificant's notification-creation window includes a Shorten URLs command that uses the to shorten any URLs in your message. URLs are clickable/tap-able in the resulting notifications, making them useful for quickly shuffling a URL between, say, your iPhone and your Mac.

You get a couple options for customizing notifications: You can choose one of nine alert sounds (or disable sounds altogether), and you can choose to use either Notificant's own onscreen notifications or, if it's installed on your Mac, . I prefer to disable Growl (which you do from within Notificant's settings screen, not from within Growl) and use Notificant's own notifications, because they're a bit more noticeable and they stay on the screen until you specifically dismiss them. (Growl has a stay-on-the-screen option, but in my experience, it doesn't always work.)

Notificant's iPhone app--which works on the iPad, but doesn't provide a native iPad interface--uses an identical process for scheduling reminders, but it actually provides more features than the Mac version. For example, you can view a list of upcoming reminders, and edit any of those reminders, and you can view a list of past reminders. And the app's icon on your Home screen can display a badge indicating the number of reminders you've missed. It's too bad the Mac version doesn't offer these features, as well; I hope a future update adds them.