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You may think you’ve reached the peak possible productivity on Windows, Mac and Linux, but if you haven’t tried this collection of timesavers, it’s time to think again.

We found software that will help you type less, enhance your efficiency, help you find a needle in a haystack, keep track of the world and probably even help you sleep better. Many of these apps are cross-platform for Windows, Mac or Linux — and best of all, most are free.

1. Nuance Dragon NaturallySpeaking

You talk and it types. Even if you’re the fastest typist in the world, you can probably talk faster, and Nuance likes to say Dragon NaturallySpeaking lets you “type at the speed of thought.” This latest version 11 doesn’t require lengthy training sessions, and its accuracy is astonishing. Pricing starts at $99 for the Home Edition, money well spent if you want to put your productivity in overdrive. The Premium Edition comes with a workable headset and is available for $154 on Amazon.

Platform: Mac, Windows
Price: $99 and up

2. KeyText

Don’t waste your time typing phrases, addresses and boilerplate text over and over. Here’s the solution: KeyText 3, an extraordinary convenience that makes it easy to slam down routine phrases with just a few keystrokes. That’s just the beginning of this powerful utility’s prowess, giving you multiple clipboards, a built-in scheduler to run programs and reminders, and automatic password filling.

Platform: Windows
Price: $30

3. f.lux

When you stare into a computer screen all day and night, you’re pretty much looking straight into a lightbulb. No wonder you’re having trouble sleeping at night — your body still thinks it’s the middle of the day. Enter f.lux — it knows what time of day it is where you’re located and starts shifting the color of your screen from the blue end of the spectrum toward a slightly reddish tinge at sundown, telling that lizard part of your brain that it’s no longer the middle of the day. Try it; you’ll probably sleep better.

Platform: Linux, Mac, Windows
Price: Free

4. Dropbox

Haven’t used Dropbox yet? Grab it now. It gives you a folder on your desktop that’s backed up in the cloud, and you get 2GB of storage space for free. It’s especially useful if you’re collaborating with others, since you can invite colleagues to access the same files. Once you discover Dropbox’s wonders, you might want to spring for the $10-per-month plan to get 50GB of storage, or even $20 per month for 100GB.

Platform: Linux, Mac, Windows
Price: Free

5. TextExpander

This text expansion tool is not only a steady mainstay on the Mac desktop, but now it’s available in iPad and iPhone/iPod Touch versions. Like KeyText 3 for Windows, TextExpander is adept at expanding text, letting you enter a few keystrokes and then pouring out boilerplate text for you. TextExpander makes creating those “snippets” a breeze with lots of easy keyboard shortcuts, and it even has a useful way of leaving open certain places within those snippets for user input.

Platform: Mac
Price: $35

6. Omnifocus

Here’s an app that’s more than a personal task manager, it’s a way of life. Whether you’re using it as part of the “Getting Things Done” (GTD) system or on its own, Omnifocus takes to-do lists to a whole new level. Fire it up with a keyboard shortcut from anywhere on your Mac, and then you can add your to-do items, categorize actions and sync them all up with iCal, or on iPhone or iPod touch versions. We especially like the way it lets you add tasks directly from an e-mail account, and then all the info in that e-mail will show up in a task, all in one step.

Platform: Mac
Price: $80

7. LastPass

This is the best password manager on the planet, and it works on browsers running on Linux, Mac and Windows machines, as well as on all mobile platforms. Type in one ultra secure password, and LastPass will remember all your other passwords, and even enter them automatically if you wish. It’s your loyal assistant, filling in forms and credit card numbers, and dreaming up impossible-to-crack passwords and automatically entering them, and best of all, it’s free. Access it from anywhere, get your password act together — this is the way to do it.

Platform: Linux, Mac, Windows
Price: Free

8. Tomboy

Here’s a note-taking app for Linux, Mac and Windows that you Linux users might already have, because it’s built into most distros. Tomboy is well-suited for everything from tiny reminders to lengthy research, and once the notetaking’s done it gives you a muscular search capability to find anything you’ve stashed away inside. It’s also adept at synchronizing, so whatever you’ve typed on one machine, you can access it from another, and search it, too.

Platform: Linux, Mac, Windows
Price: Free

9. Pidgin

Do a lot of instant messaging? Even if you use a dozen different platforms to chat with your friends and neighbors, the Pidgin multi-chat client has you covered. You only have to enter your credentials one time for AIM, Google Talk, IRC, and many others, and then Pidgin handles them all. Working equally well on Linux, Mac and Windows, this baby’s been around long enough to attract third parties to write plug-ins that make it even more convenient.

Mac OS X users should also take a look at the very similar free instant messaging application Adium, which is based on many of the same libraries as Pidgin.

Platform: Linux, Mac, Windows
Price: Free